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Union Reform, Performance Pay, and New Teacher Supply: Evidence from Wisconsin’s Act 10 * E. Jason Baron Version: January 16, 2019 Abstract Despite the pervasive debate surrounding teachers’ unions and their impacts on teacher recruit- ment, the causal effect of unions on new teacher supply has not been rigorously examined due to a lack of variation in public sector unionism. To fill this gap in the literature, this study exploits recent variation in union strength induced by the enactment of Wisconsin’s Act 10, a landmark law that severely reduced the influence of teachers’ unions in the state and gave school districts the freedom to redesign their compensation schemes. Immediately following the law, the majority of school districts in Wisconsin eliminated rigid unionized compensation schemes and moved to negotiate salaries with individual teachers based on performance. As a result, the compensation of teachers with high-value-added prior to Act 10 rose more than that of teachers with low-value-added in school districts that switched to flexible compensa- tion. To test whether these changes in compensation impacted the quantity and the quality of new teacher supply, I compare the quantity of individuals completing a teaching degree in Wisconsin institutions before and after Act 10 and relative to those in similar states in a difference-in-differences framework. I find that Act 10 led to a 20% increase in the number of awarded teaching degrees. This effect was entirely driven by the most selective universities, which suggests that the quality of the prospective teacher pool in Wisconsin increased as a result of the union reform. Keywords: Teachers’ Unions, New Teacher Supply, Performance Pay, Major Selection JEL Classification: I20, I28, J24, J31, J45, J51 * I would like to thank Shawn Kantor, Carl Kitchens, Luke Rodgers, Anastasia Semykina, David Welsch, and numerous conference participants at Florida State University and other institutions for valuable comments and support. All mistakes and conclusions are my own. Department of Economics, Florida State University, 288 Bellamy Building, Tallahassee, FL 32306, United States. Tel.: (850) 644-5001; E-mail: [email protected].

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Page 1: Union Reform, Performance Pay, and New Teacher Supply: … · 2019-03-11 · Critics of teachers’ unions argue that unionized compensation schemes, known as salary sched- ules,

Union Reform, Performance Pay, and New TeacherSupply: Evidence from Wisconsin’s Act 10∗

E. Jason Baron†

Version: January 16, 2019

Abstract

Despite the pervasive debate surrounding teachers’ unions and their impacts on teacher recruit-

ment, the causal effect of unions on new teacher supply has not been rigorously examined due

to a lack of variation in public sector unionism. To fill this gap in the literature, this study

exploits recent variation in union strength induced by the enactment of Wisconsin’s Act 10,

a landmark law that severely reduced the influence of teachers’ unions in the state and gave

school districts the freedom to redesign their compensation schemes. Immediately following

the law, the majority of school districts in Wisconsin eliminated rigid unionized compensation

schemes and moved to negotiate salaries with individual teachers based on performance. As

a result, the compensation of teachers with high-value-added prior to Act 10 rose more than

that of teachers with low-value-added in school districts that switched to flexible compensa-

tion. To test whether these changes in compensation impacted the quantity and the quality

of new teacher supply, I compare the quantity of individuals completing a teaching degree

in Wisconsin institutions before and after Act 10 and relative to those in similar states in a

difference-in-differences framework. I find that Act 10 led to a 20% increase in the number of

awarded teaching degrees. This effect was entirely driven by the most selective universities,

which suggests that the quality of the prospective teacher pool in Wisconsin increased as a

result of the union reform.

Keywords: Teachers’ Unions, New Teacher Supply, Performance Pay, Major Selection

JEL Classification: I20, I28, J24, J31, J45, J51

∗I would like to thank Shawn Kantor, Carl Kitchens, Luke Rodgers, Anastasia Semykina, David Welsch, andnumerous conference participants at Florida State University and other institutions for valuable comments and support.All mistakes and conclusions are my own.†Department of Economics, Florida State University, 288 Bellamy Building, Tallahassee, FL 32306, United States.

Tel.: (850) 644-5001; E-mail: [email protected].

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1 Introduction

Teacher quality has been shown to be one of the most important school-related inputs in the educa-tion production function (Rivkin et al., 2005; Rockoff, 2004). Furthermore, teachers’ impacts onstudents are long-lasting. All else equal, students assigned to high-quality teachers are more likelythan students assigned to low-quality teachers to go to college and attain higher earnings (Chettyet al., 2014b). The established importance of teachers to both the short- and long-run outcomes ofstudents has led policymakers and scholars alike to explore policies that are most likely to attracthigh-quality individuals to the teaching profession.

Despite the documented importance of teachers to student learning, little is known about poli-cies that foster an environment whereby qualified individuals are lured into the profession. Thisissue has gained growing attention in recent years as school districts across the country continueto face challenges in attracting new individuals to teaching. For instance, data gathered by theACT show that pursuing a career in education has dramatically lost popularity among ACT-testedhigh school students since 2008. Indeed, decreasing interest in the teaching profession is oftencited as one of the main drivers of the current wave of teacher shortages impacting school districtsthroughout the country (Sutcher et al., 2016). Moreover, in the 2017-18 academic year, high schoolstudents who expressed interest in becoming teachers had significantly lower ACT test scores thanstudents who expressed no interest in joining the profession (Croft et al., 2018).

While numerous policies to improve selection into teaching have been proposed, teachers’unions are often at the forefront of these discussions.1 As of 2015, roughly half of elementary andsecondary school teachers belonged to a union (Hirsch and Macpherson, 2015). Teachers’ unionsinfluence public education in the United States mainly through the collective bargaining process.2

They seek to maximize the utility of their members by bargaining with local school boards forhigher wages and benefits, job security, and more favorable working conditions such as smallerclass sizes (Lovenheim, 2009). Additionally, unions often bargain for compensation schemes thatare based solely on seniority and educational attainment, rather than individual quality, and oftenprotect teachers with longer tenure from layoffs and less desirable school assignments (Strunket al., 2017; West and Mykerezi, 2011).

Critics of teachers’ unions argue that unionized compensation schemes, known as salary sched-ules, fail to differentiate among teachers based on their quality or subject-area of expertise and thus

1Improving selection into teaching is clearly not the only way to improve overall teacher quality. Policies suchas performance bonuses, better professional development, and termination of low-productivity teachers are amongthe many alternatives proposed. However, improving the quality of new teacher supply may be a more cost effectivepolicy since it avoids the costs of exposing students to low-quality teachers and compensating incumbent teachers forthe increased risk of termination (Jacob et al., 2018; Rothstein, 2015).

2While teachers’ unions can also influence public education through their involvement in the political arena, theirmain role is that of bargaining agents for public school teachers (Cowen and Strunk, 2015).

1

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may distort the ability of school districts to attract teachers in specialized fields with higher outsideoptions (West, 2013). A simple Roy model of occupational choice predicts that high-quality work-ers will be pushed out of a profession that compresses pay-for-aptitude. Hoxby and Leigh (2004)test these predictions in the education sector and show that the compression in wages resultingfrom collective bargaining over compensation schemes during the second half of the twentiethcentury explains much of the decline in entry of high-aptitude women into the teaching profession.

Additionally, salary schedules are structured as back-loaded compensation systems: that is,educators are compensated for lower starting salaries with steady, certain salary raises and gener-ous retirement benefits. Yet low starting salaries are the main reason most high school studentsare not interested in teaching (Croft et al., 2018).3 Finally, while more attractive compensationis often proposed as a promising policy to recruit better-qualified teachers, Figlio (2002) showsthat this relationship is only true in non-unionized public schools, perhaps because these schoolslink compensation and job protections to performance and thus differentially reward high-qualityteachers.

Alternatively, proponents of teachers’ unions argue that unions empower their members bygiving them a “voice” through which they can influence various aspects of the teaching profes-sion (Freeman and Medoff, 1984). In addition, they argue that eliminating the salary schedule andseniority-based job protections would discourage individuals from joining the profession. Previousstudies have shown that individuals who select into the teaching profession are more risk averseand place a larger premium on job security than similar college graduates (Bowen et al., 2015;Rothstein, 2015). In fact, one of the biggest challenges in recruiting high-quality individuals tothe teaching profession has been a perceived decline in job security and job satisfaction (Croftet al., 2018). Given imperfect information regarding an individual’s own ability to teach, as well asthe perceived inability of school districts to accurately measure teacher quality (Rothstein, 2015),certainty over the stream of future earnings, job security, and the ability to influence working con-ditions through collective bargaining may encourage high-quality individuals to pursue a teachingcareer.

Despite the pervasive debate surrounding teachers’ unions and their effects on teacher recruit-ment, a rigorous examination of the impact of teachers’ unions on new teacher supply has not yetbeen conducted. Teacher unionization expanded dramatically during the 1960s when various statespassed favorable collective bargaining legislation for government workers and remained stable un-til recently (Frandsen, 2016). A lack of granular data on new teacher supply at the time teacherunionization fist expanded coupled with a lack of variation in unionization status over time hasimpeded an empirical analysis of the effects of teachers’ unions on new teacher supply.

3The literature has shown that incumbent teachers also prefer an equivalent increase in current wages to the guar-anteed stream of income that large deferred compensation packages offer (Fitzpatrick, 2015).

2

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This paper exploits recent variation in union strength to fill this gap in the literature. In 2011,in an effort to address a looming state budget deficit resulting from the Great Recession, Wisconsinenacted the Budget Repair Bill (or Act 10). This landmark law severely reduced the influence ofpublic sector unions in the state by limiting the scope of union negotiations and restricting theirfundraising abilities.

Figure 1 shows the dramatic decline in public sector union membership in Wisconsin followingthe enactment of Act 10 in 2011. Roughly half of public sector employees in Wisconsin belongedto a union prior to 2011, well above the national average of 35%. Between 2011 and 2012, Wis-consin’s public sector union membership decreased from 50% to 37% and continued to plummetin the following years to approximately 22% in 2016. In contrast, the national average remainedroughly constant at 35%. This effect was mainly driven by declines in the membership of teachers’unions in the state. Reports from the local press indicate that the Wisconsin Education AssociationCouncil (WEAC), the state’s largest teachers’ union, experienced a decline in membership of over50%, or 60,000 members, from 2011 to 2015.4

Wisconsin’s weakening of teachers’ unions brought notable changes to the teaching professionin the state. Perhaps the most important provision of Act 10 for Wisconsin’s school districts wasthe reduction in the scope of collective bargaining. Given that the law prohibited union negotiationsover compensation schemes and layoff procedures, school districts were awarded the possibility toindividually negotiate pay and job protections with teachers. As a result, immediately followingthe law many school districts eliminated rigid salary schedule schemes and moved to negotiatingsalaries with individual teachers. Although a lot of variation arose in the way districts designedtheir new compensation schemes, most districts sought to tie pay to performance (Heneman et al.,2018). Similarly, with job protections outside the scope of collective bargaining, teaching perfor-mance quickly replaced seniority as the leading factor in layoff decisions at most school districts.5

Previous studies have shown that after Act 10, the compensation of teachers with high value-added prior to the reform rose more than did that of low-value-added teachers in school districtsthat switched to flexible compensation.6 The differences in salaries that arose among school dis-tricts after the union reform changed teachers’ incentives to work in a given district. Following thelaw high-value-added incumbent teachers flowed into school districts that adopted flexible pay and

4See, for example: Beck (2015), “WEAC Turns to Local Focus After Massive Membership Loss,” Wisconsin StateJournal. Accessed at: http://host.madison.com/wsj/ (August 11, 2017).

5These changes were documented in a series of articles by the Milwaukee Journal Sentinel following a survey ofsuperintendents in Wisconsin regarding the perceived effects of Act 10 on their districts. See, for example: Umhoefer,D. and S. Hauer (2016), “In wake of Act 10, fears rise about growing divide in arms race for teachers,” MilwaukeeJournal Sentinel. Accessed at: http://www.jsonline.com/ (March 11, 2017).

6Teacher value-added has been shown to be a good measure of teacher quality (Chetty et al., 2014a). It is definedas a teacher’s contribution to the growth of students’ test scores once all other determinants of student learning havebeen considered.

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tied compensation to performance, while low-value-added teachers moved to school districts thatkept their rigid salary schedules (Biasi, 2018).

While responses of incumbent teachers to the union reform have been widely studied (Baron,2018; Biasi, 2018; Roth, 2017; Litten, 2016), the effects of Act 10 on prospective teachers remainunexplored. However, just as they impacted the incentives of incumbent teachers, the changestriggered by Act 10 to both compensation schemes and layoff procedures could fundamentallyalter the decision of prospective workers to enter the teaching profession. Through an examinationof the impact of Wisconsin’s union reform on the quantity and the quality of individuals completinga teaching degree in the state, this paper seeks to shed light on the effect of teachers’ unions onnew teacher supply.

Examining this question presents identification challenges that I address using multiple datasetsand research designs. The passage of Act 10 provides the policy-induced variation that I exploitthroughout the paper. I begin by collecting state-level data on the number of enrollees in TeacherPreparation Programs (TPPs). A TPP is a state-approved course of study whose completion sig-nifies that a student has met all educational requirements for initial certification to teach in thestate’s K-12 system. Using this dataset, I present descriptive evidence of changes in the number ofindividuals enrolled in a TPP in Wisconsin before and after Act 10 and relative to similar states.

I complement the state-level descriptive analysis with more detailed institution-level data fromthe Integrated Postsecondary Education Data System (IPEDS) on the number of individuals grad-uating with a postsecondary degree in teaching. While enrollment in TPPs is an attractive measureof immediate changes in potential new teacher supply, not all students who enroll in a TPP com-plete it. Therefore, complementing the enrollment measure with the number of awarded teachingdegrees may help paint a broader picture regarding the effects of deunionization on new teachersupply. Using this dataset, I compare the number of awarded teaching degrees at Wisconsin insti-tutions before and after Act 10 and relative to similar states in a difference-in-differences (DID)framework. I additionally estimate an event study specification to describe the dynamics of theimpacts of Act 10 and to directly test whether or not Wisconsin institutions and those in controlstates followed similar trajectories in new teacher supply prior to the enactment of the law.

Finally, to shed light on the impacts of Act 10 on the quality of potential teachers, I examineheterogeneity in the effects of the law by institutional selectivity. I use an institution’s 25th and75th percentiles of freshman ACT composite scores as proxies for institutional selectivity. Whilework attempting to link observable characteristics at the time of hire to future teacher effectivenessis still ongoing (Rothstein, 2015; Rockoff et al., 2011), proxies for the selectivity of an individual’sundergraduate institution are correlated with future teaching performance and have been widelyused in the literature (Kraft et al., 2018; Jacob et al., 2018; Angrist and Guryan, 2008; Hoxby andLeigh, 2004; Figlio, 2002; Figlio and Rueben, 2001; Ehrenberg and Brewer, 1994).

4

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In general, I find that the number of prospective teachers in Wisconsin increased as a result ofAct 10. Estimates from the event study show that institutions in Wisconsin and those in controlstates had similar trajectories in the number of teaching degrees prior to the union reform. How-ever, following the enactment of Act 10, the number of awarded teaching degrees at a given Wis-consin institution increased by approximately 20 relative to institutions in the control states. Thiseffect corresponds to a 20% increase relative to the number of annual teaching degrees awarded atthe average Wisconsin institution prior to Act 10. Exploring heterogeneity in the effects of the lawby institutional quality, I find that this effect was entirely driven by the most selective universities.This finding suggests that the quality of the prospective teacher pool in Wisconsin increased as aresult of the union reform. A number of robustness checks are conducted to ensure that the resultsare not sensitive to the choice of control group and specification.

This study makes three main contributions to the literature. First, it adds to the extensive lit-erature that attempts to identify efficient teacher recruitment policies. For instance, Kraft et al.(2018) show that the repeal of teacher tenure protections across states in recent years have reducedthe number of individuals completing a teaching degree at less selective universities. Jones andHartney (2017) find that school districts that adopt performance-based compensation are able torecruit a larger number of teachers from more selective universities than districts with more rigidcompensation schemes. Rothstein (2015) shows that performance-based compensation and reten-tion policies can significantly improve selection into teaching when accompanied with substantialsalary increases. Figlio and Rueben (2001) show that a state-level reduction in school spendingthrough tax limits significantly reduces the quality level of entrants into a state’s teaching force.This paper contributes to this literature by demonstrating that Wisconsin’s weakening of teach-ers’ unions increased both the quantity and the quality of prospective teachers in the state. Theresults here also suggest that new high-quality individuals can be lured into the teaching profes-sion by enacting compensation schemes that reward performance rather than seniority and yearsof educational attainment alone.

This study also adds to the literature on how human capital investment decisions respond toshocks in the real economy. A number of studies have examined whether students are sensitive tothe local labor market returns of particular college majors. Long et al. (2015) find that an increasein the wages offered by particular occupations is associated with subsequent increases in the com-pletion of college majors associated with those occupations. Their paper provides evidence thatstudents’ college major choices are indeed influenced by wage information that is received be-fore or during their college career. Weinstein (2017) provides evidence that college major choiceresponds to local labor market conditions by showing that universities in areas more exposed tosectoral shocks experience greater changes in sector-relevant majors. For instance, he finds thatafter the dot-com crash, there was a sharp decline in computer science degrees at research univer-

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sities in high computer employment areas, but there was no effect at research universities in areaswith low computer employment shares. My paper provides evidence that the education sectorfunctions like any other labor market - an increase in the wages of high-quality teachers in Wis-consin is associated with a subsequent increase in the completion of teaching degrees at selectiveuniversities in the state.

Finally, this paper adds to the small literature examining the impact of teachers’ unions onstudent outcomes.7 Exploiting plausibly exogenous variation in the timing of exposure to Act 10across Wisconsin school districts, Baron (2018) shows that the law led to a large decline in studenttest scores in the short run. While an examination of the short-run impacts of teacher deunion-ization on student achievement represents an important first step in understanding the effects ofdeunionization on student success, an analysis of the long-run stable effects that arise after Act10’s initial shock is of first-order importance. In particular, the general equilibrium effects of Act10 on student outcomes will depend on how it affected new teacher supply. Even though Act 10had negative, disruptive effects on student achievement in the short run, the present study suggeststhat the reform may have led to an increase in the quality of prospective teachers in the state. Ageneral equilibrium analysis of the effects of Act 10 on student success that incorporates thesechanges in new teacher supply represents a promising avenue for future research.

2 Background

2.1 Unions in Wisconsin Pre-Act 10

In 1959 Wisconsin became the first state to grant teachers’ unions the right to collectively bargain.At the time teachers’ unions served as professional and political advocates for teachers, but hadno formal bargaining rights. From the time they were granted the right to collectively bargain,until 2011, teachers’ unions operated under a relatively favorable regulatory environment. Unionshad the ability to collectively bargain with local school boards over many aspects of the teachingprofession such as working conditions, teachers’ compensation schemes, and layoff procedures.

For instance, prior to 2011 teachers’ unions bargained for seniority-based compensation andjob protections. As a result, all unionized districts in Wisconsin paid their teachers according toa salary schedule, where years of experience and level of education were generally the two soledeterminants of compensation. Individual-specific salary negotiations were prohibited. In otherwords, two teachers in a school district with the same level of education and experience wouldusually get paid the same amount, regardless of variation in teacher quality or subjects taught(Biasi, 2018). Furthermore, unions often bargained for policies that protected teachers with longer

7For influential papers in this literature see Lovenheim and Willen (2018), Lovenheim (2009), and Hoxby (1996).

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tenure from layoffs or less desirable school assignments. As an example, policies such as Last-In-First-Out (LIFO) in which teachers with the least seniority were the first ones to be laid off whena school district determined it must reduce staff were common prior to Act 10.8

2.2 Wisconsin’s Act 10

On June 29, 2011, Wisconsin enacted the Wisconsin Budget Repair Bill, or Act 10, which includeda number of provisions that weakened the power of teachers’ unions in the state. First, the lawrestricted the scope of collective bargaining to negotiations over inflation adjustments to total basewages for most state employees.9 Second, the law implemented a right-to-work measure thatprohibited unions from deducting dues from paychecks and allowed employees to refuse to payagency fees while remaining in the bargaining unit. Third, the Act restricted the length of collectivebargaining agreements (CBAs) to one-year periods.

Fourth, the law created a new system of certification elections. Prior to Act 10, once a collectivebargaining unit elected a labor organization as its representative, the organization remained theunit’s representative unless a petition was supported for a new election to decertify. Act 10 requiredan annual certification election for a union to maintain legal status. If less than a majority ofmembers in the bargaining unit vote to keep the union, then the union is decertified.

Finally, prior to the enactment of Act 10 state employees paid on average 6% of their annualhealth insurance premiums, and most paid little or nothing toward their pensions. Act 10 requiredstate employees to contribute at least 12.6% of their average annual health premiums and 50%of their annual pension contributions. When considered simultaneously, it is clear that the lawseverely reduced the influence of teachers’ unions in Wisconsin by limiting the scope of union ne-gotiations, increasing the costs to unionization, and altering the funding structure of union activity.

It is important to understand why a bill designed to address a budget deficit would target the in-fluence of public sector unions. In addition to Act 10, Wisconsin imposed a significant reduction instate appropriations to school districts under the 2011-13 biennial budget known as Act 32.10 Act10 and Act 32 were proposed concurrently to address the state’s looming budget deficit. The archi-tects of Act 10 explained that by allowing school administrators to make decisions unconstrainedby teachers’ unions, its provisions would allow school districts to generate enough savings to off-set the decrease in state aid, which in turn would help the state reduce its deficit. In Section 4.2,

8Author’s review of pre-Act 10 collective bargaining agreements.9Act 10 excluded public safety employees from its provisions.

10School districts in Wisconsin derive a large part of their total revenue from two main sources: state aid andproperty taxes (88% in the 2014-15 academic year). Most state aid is delivered to school districts as equalization aid.Act 32 decreased funding for school districts in two ways. First, it reduced equalization aid by 8.4% in the 2011-12academic year (relative to 2010-11). Second, it reduced each district’s revenue limits, which restrict the amount ofrevenue a district can raise from state aid and property taxes, by 5.5%. The reduction in revenue limits preventedschool districts from simply raising school levies to make up for the loss in aid.

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I discuss in more detail whether Act 32 poses a threat to identification of the effects of Act 10 onnew teacher supply.

2.3 Effects of Act 10 on Wisconsin’s Teacher Workforce

In order to understand how Act 10 might impact new teacher supply, it is useful to begin bydescribing the various changes that the reform brought to Wisconsin’s teacher workforce. Perhapsthe most important provision of Act 10 for Wisconsin’s school districts was the reduction in thescope of collective bargaining. Given that the law restricted the scope of collective bargaining tonegotiations over inflation adjustments to base wages, school districts were awarded the possibilityof individually negotiating pay with teachers.

As a result, immediately following the law many school districts eliminated rigid salary sched-ule schemes. For instance, as of December 2015, roughly half of school districts had discontinuedthe practice of determining teacher compensation solely through a salary schedule and had movedto negotiating salaries on an individual basis. These changes immediately triggered significant dif-ferences in pay among teachers whose compensation would have been identical in the years priorto Act 10 (Biasi, 2018). While a lot of variation arose in the way districts designed their new com-pensation schemes, a majority of districts sought to tie pay to teacher performance (Heneman et al.,2018). Similarly, with job protections now outside the scope of collective bargaining, policies suchas LIFO have been gradually eliminated in most school districts. After conducting a survey of su-perintendents in Wisconsin, the Milwaukee Journal Sentinel reported that performance has nowreplaced seniority as the leading factor in layoff decisions in the majority of school districts.11

To demonstrate the effects of these changes on the education sector in Wisconsin, I use anindividual-level dataset published annually by the Wisconsin Department of Public Instruction(WDPI). This dataset contains detailed information on the universe of Wisconsin public schoolteachers. It includes covariates such as each teacher’s first and last name, district and school ofemployment, birth year, total salary and fringe benefits, and years of teaching experience. Thisinformation allows me to construct variables such as the share of teacher retirements, the shareof interdistrict teacher transfers, and teacher compensation in Wisconsin’s public school districtsfrom 2005-06 through 2015-16.12 Figure 2 presents the time series of these variables before and

11These interviews can be found in a series of articles by the Milwaukee Journal Sentinel. In these articles, theauthors present findings from a detailed survey of school superintendents regarding the perceived effects of Act 10 ontheir districts. See, for example: Umhoefer, D. and S. Hauer (2016), “In wake of Act 10, fears rise about growingdivide in arms race for teachers,” Milwaukee Journal Sentinel. Accessed at: http://www.jsonline.com/ (March11, 2017).

12I follow Roth (2017) and estimate the teacher retirement rate as the attrition rate for retirement-eligible teachers- those older than 55 years old, the minimum early retirement age for Wisconsin public school teachers. Thus, theretirement rate in year t is computed as the fraction of total teachers in Wisconsin in year t who are eligible to retireand leave the sample in year t+1. The teacher turnover rate in year t is computed as the proportion of all teachers who

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after 2011-12, the academic year in which Act 10 came into effect. Clear changes in the trends ofthese measures arise following the enactment of the law.

2.3.1 Teacher Retirements

Panel (a) of Figure 2 shows that the average share of teachers retiring increased by roughly 115%following the enactment of the law.13 Roth (2017) examines teacher retirements after Act 10 inmore detail and argues that the law created short-run incentives for eligible teachers to retire priorto the expiration of their district’s pre-existing CBA. Act 10 required school districts to honorcollectively bargained (district-provided) post-retirement benefits such as retiree health care andlife insurance for teachers who retired prior to the end of the pre-existing CBA in place at theirdistrict. However, with post-retirement benefits now outside the scope of collective bargaining,continuation of these benefits was left at the discretion of the district once the pre-existing CBAexpired. Given uncertainty about whether or not districts would discontinue these benefits, a largenumber of eligible-to-retire teachers chose to retire and secure benefits under their current CBA.Continuing to work meant risking losing these benefits.

2.3.2 Teacher Salaries

Panel (b) shows that after slowly rising in the years prior to Act 10, real average teacher compen-sation (salary + fringe benefits) decreased following the law. The drop in teacher compensationappears to be a combination of a reduction in average teacher salaries and fringe benefits. The de-cline in average fringe benefits is predictable, as it was mandated by the law. Some of the declinein average salaries may simply reflect the fact that older, higher paid teachers retired following Act10.

Indeed, while compensation may have declined on average, previous studies have documentedsubstantial heterogeneity in compensation changes by teacher quality and experience levels. Biasi(2018) shows that after Act 10, the compensation of teachers with high-value-added prior to thereform rose more than did that of low-value-added teachers in school districts that abandoned thesalary schedule and switched to more flexible, performance-based compensation. These findingsdemonstrate that school districts are in fact able to identify high-value-added teachers and whengiven the opportunity to do so choose to compensate them accordingly.

in year t transferred to a new public school district. When computing aggregate variables from the individual-leveldataset, I weight teachers by their corresponding full-time equivalent (FTE) units. Total salary and fringe benefits areconverted to real dollars using 1982-84 as the base period.

13Recall that the retirement rate for year t is computed as the fraction of total teachers in year t who are eligibleto retire and leave the sample in year t + 1. The fact that there is a sharp increase in the number of eligible-to-retireteachers in 2010-11 who leave the sample in 2011-12 suggests these teachers retired following the enactment of Act10 (right before the 2011-12 academic year).

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Consistent with Biasi’s findings, Litten (2016) documents a reduction in the return to tenurefollowing Act 10. Given the ability of districts to link performance to compensation rather thanseniority and educational attainment alone, younger teachers with relatively higher value-added ex-perienced wage increases after Act 10 while older teachers with relatively lower value-added suf-fered declines in compensation. Panel (c) documents this heterogeneity in compensation changesby teaching experience levels. While average compensation sharply decreased for the cohort ofteachers with the most experience (possibly due to teacher retirements and a district’s newly-granted ability to tie compensation to performance), real average compensation for the cohort ofteachers with the lowest levels of experience at the time the law was enacted has steadily increased.

2.3.3 Interdistrict Teacher Transfers

Panel (d) plots the time series of the share of interdistrict teacher transfers, a measure of teacherturnover, before and after 2011-12. The share was relatively low in the years prior to the enactmentof Act 10 (around 1%). This was likely the result of union contracts that incentivized teachers toremain in the same school district throughout their careers with seniority-based compensation andjob protections.14 However, the removal of incentives that tied educators to their school districts,as well as the differences in salaries that arose among school districts following Act 10, could havechanged the incentives of teachers to work in a given school district.

In fact, the change in the trend in Panel (d) is clear immediately following Act 10’s implemen-tation. The share of interdistrict transfers increased by roughly 100% in 2011-12 and continued toincrease thereafter (to approximately 3% in 2014-15). Biasi (2018) examines post-Act 10 teachers’movements across districts and shows that incumbent teachers with high-value-added prior to Act10 responded to the increase in salaries at school districts that adopted flexible pay and flowed intothese districts.

2.3.4 Potential Effects on New Teacher Supply

Altogether, previous research has shown that following the enactment of Act 10, districts in Wis-consin were able to attract high-value-added incumbent teachers by tying compensation to per-formance and raising the salaries of high-value-added teachers. While responses of incumbentteachers to Wisconsin’s union reform have been widely studied, the effects of Act 10 on new

teacher supply remain unexplored. Yet the changes in compensation and job security induced by

14Prior to Act 10, when making compensation or layoff decisions districts generally defined seniority as the numberof years of teaching experience within a particular school district. Furthermore, union contracts often rejected awardingteachers full credit for years of experience gained at other school districts. These policies created strong incentives forteachers to remain in one school district throughout their careers, as they risked losing seniority-based benefits if theytransferred school districts.

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Act 10 could fundamentally alter both the quantity and the quality of new individuals entering theteaching profession.

An individual will pursue a teaching major if teaching yields the highest expected utility amongall potential professions. In this context, expected utility is a function of the profession’s relativeexpected wages, benefits, and other non-pecuniary aspects of the profession such as working con-ditions and personal satisfaction.15 Teacher deunionization can impact all inputs of the expectedutility function.

A Roy model of occupational choice predicts that high-aptitude workers will be pushed outof a profession that compresses pay-for-aptitude (Roy, 1951). The intuition for this result is thatsalary schedules over-compensate low-quality teachers and under-compensate high-quality ones.Hoxby and Leigh (2004) test these predictions and show that the compression in wages resultingfrom teacher unionization during the second half of the twentieth century explains much of thedecline in entry of high-aptitude women into the teaching profession. Therefore, as more districtsin Wisconsin continue to enact merit-based compensation schemes new high-quality individualsmay be lured into the profession. Similarly, Jones and Hartney (2017) show that school districtsthat adopt performance-based compensation are able to recruit a larger number of teachers frommore selective universities than districts with more rigid compensation schemes.

The reduction in the return to tenure and the simultaneous increase in compensation for high-value-added teachers resulting from Act 10 could further attract new highly-qualified individualsto teaching. There a number of studies showing that higher pay and performance-based retentionpolicies will improve selection in an environment that post-Act 10 Wisconsin resembles. Forinstance, Rothstein (2015) shows that performance-based compensation and retention policies cansignificantly improve selection into teaching when accompanied with substantial salary increases.Figlio (2002) finds that a school’s probability of hiring qualified teachers increases with higherteacher salaries at non-union schools but not at unionized ones, perhaps because non-unionizedschools differentially reward high-quality teachers in both pecuniary and non-pecuniary ways (suchas smaller class sizes). Finally, Kraft et al. (2018) show that the repeal of teacher tenure protectionsacross states in recent years has reduced the number of individuals completing a teaching degreeat less selective universities.

On the other hand, changes brought about by Act 10 might discourage qualified individualsfrom entering the teaching profession through several mechanisms. Previous studies have shownthat individuals who select into the teaching profession are more risk averse and place a largerpremium on job security than similar college graduates (Bowen et al., 2015; Rothstein, 2015). Infact, one of the biggest challenges in recruiting high-quality individuals to the teaching profession

15While the cost of choosing a particular major is clearly an input in the expected utility function, it is unlikely tobe affected by the union reform and is thus omitted from the discussion.

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has been a perceived decline in job security and job satisfaction (Croft et al., 2018). Given imper-fect information regarding an individual’s own ability to teach as well as the perceived inability ofschool administrators to accurately measure teacher quality, increased uncertainty over the streamof future earnings and job security may discourage risk averse, highly-qualified individuals fromjoining the profession.

Moreover, teachers’ unions have been shown to empower their members by giving them a“voice” through which they can influence various aspects of the teaching profession (Freeman andMedoff, 1984). Qualified individuals may be less likely to pursue a teaching degree if they perceivethat deunionization has hindered their ability to influence their workplace. Finally, Act 10 mayhave discouraged high-quality individuals from pursuing a teaching degree if potential entrantsnow perceive teaching as a less enjoyable career (Kraft et al., 2018). Perhaps due to the politicaldiscourse surrounding it, Act 10 was seen by many as an “attack on the teaching profession.”Widely covered teachers’ protests following the announcement of the bill, which included as manyas 100,000 protestors and continued from February 2011 until June 2011, may have signaled topotential entrants that the reform was detrimental to the teaching profession and one’s quality oflife as a teacher.

The net effect of deunionization on both the quantity and the quality of prospective teachers willdepend on whether or not the increase in compensation for high-quality teachers and the enactmentof merit-based schemes outweigh the increase in risk associated with teacher deunionization. Thetheoretical ambiguities described in this section highlight that the net effect of Act 10 is largely anempirical question.

3 State-Level Descriptive Evidence

Ideally, one would measure a state’s new teacher supply as the total number of fully licensedcandidates that applied for a K-12 teaching position in the state for the first time. While such ameasure is not publicly available, the number of individuals in a state who enroll in and completea TPP can be used as a proxy for the number of new entrants.16 TPPs throughout the countrygenerate the pool of new teachers that enter the profession each year. In most states, individualspursuing an initial teacher certification must complete a bachelor’s degree and a state-approvedTPP.

While enrollment in TPPs can be used as a proxy for new teacher supply, simply regressing thenumber of students in a state who are enrolled in a TPP on a measure of the strength of teachers’unions in that state would likely yield a biased estimate due to either simultaneity or omitted-

16Estimates in the literature typically find that roughly 70%-90% of newly-minted teachers enter the classroomwithin a year of completing their teacher preparation (Sutcher et al., 2016).

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variable bias. As an example, states in which individuals are particularly passionate about theteaching profession may have both a larger share of postsecondary enrollment in teaching and bemore likely to have strong teachers’ unions. Ideally, to solve the endogeneity concern, one wouldrandomly assign teachers’ unions to states and measure subsequent differences in TPP enrollment.Given the infeasibility of such an experiment, I instead exploit variation induced by the enactmentof Wisconsin’s Act 10.

The empirical approach in this study compares the change in the number of TPP enrollees andcompleters in Wisconsin before and after Act 10 and relative to control states. Throughout thepaper, I use three distinct sets of nearby states as control groups: states that border Wisconsin (IL,IA, MI, and MN), henceforth “border states”; states in the East North Central Division (IL, IN, MI,and OH), henceforth “division states”; and states in the Midwest Region (IL, IN, MI, OH, MN,IA, MO, ND, SD, NE, and KS), henceforth “Midwestern states.”17 The map in Figure 3 depictsthese control groups. Using local controls has been used in many other settings (Feigenbaum et al.,2018; Dube et al., 2010; Holmes, 1998). The intuition behind this approach is that nearby statesought to have a more similar higher education sector to Wisconsin than states in other regions ofthe country and thus may follow similar trends in prospective teacher supply prior to the enactmentof Act 10.

I begin by presenting state-level descriptive evidence of changes in the share of postsecondarystudents who are enrolled in a TPP in Wisconsin before and after Act 10 and relative to the threecontrol groups.18 While the quality of new teacher supply is of first-order importance, a declinein the number of students in TPPs is often cited as one of the main drivers of the current wave ofteacher shortages impacting school districts throughout the country (Sutcher et al., 2016). Giventhe large negative impacts that teacher shortages can have on student outcomes, it is crucial tounderstand which types of policies either encourage or discourage students from enrolling in aTPP.19

Trends in the share of postsecondary students in the state who are enrolled in a TPP are shownin Figure 4 separately for Wisconsin and the respective control groups. The figure shows thatWisconsin’s share was lower than either of the control groups and proceeded in a similar pattern inthe years prior to the enactment of Act 10. The figure also shows a slower decline in enrollment inTPPs in Wisconsin relative to each control group starting in 2012, the first year under the new Act

17Census Regions are groupings of states that subdivide the U.S. for presentation of census data. There are fourcensus regions: Northeast, Midwest, South, and West. Each of the four census regions is divided into two or morecensus divisions. Wisconsin belongs to the Midwest Region and to the East North Central Division.

18Information on the number of students who have been admitted to a TPP comes from the Department of Education(DOE) and is available from 2008-09 through 2015-16. State-level enrollment in postsecondary education is publishedannually by the National Center for Education Statistics (NCES).

19For instance, teacher shortages could lead to increases in class sizes which have been shown to have large, negativeimpacts on student achievement (Angrist and Lavy, 1999; Finn and Achilles, 1990).

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10 regime. By the 2012-13 academic year TPP enrollment was higher in Wisconsin than in each ofthe control groups, and remained higher for the remainder of the sample period. This descriptiveevidence begins to suggest that Wisconsin would have suffered a much sharper decline in TPPenrollment had Act 10 not been enacted.

4 Institution-Level Analysis

4.1 Data

To formally estimate the impact of Act 10 on the supply of prospective teachers, I complementthe state-level descriptive analysis with more detailed institution-level information from IPEDS onthe number of graduates from university-based TPPs.20 While enrollment in TPPs is an attrac-tive measure of immediate changes in potential new teacher supply, not all students who enrollin a TPP complete it.21 Therefore, complementing the enrollment measure with the number ofawarded postsecondary teaching degrees may help paint a broader picture regarding the effects ofdeunionization on new teacher supply.

I restrict the sample to all degree-granting public and private universities located in Wisconsinand in the control states and calculate the number of awarded teaching degrees at each institutionas the total number of students who graduated with a bachelor’s degree (first or second major)in teaching. To isolate teaching degrees, I use the Classification of Instructional Programs (CIP)codes used by Kraft et al. (2018).22 However, the results in the paper are robust to alternativedefinitions such as that used by Park et al. (2018),23 or simply using the total number of educationdegrees instead.24

20IPEDS collects institution-level data from each postsecondary institution that participates in the federal studentfinancial aid program. Most students pursuing a teaching degree are enrolled in university-based TPPs. For instance,in the 2012-13 academic year, only 6% of teaching candidates were enrolled in a TPP not based at a higher educationinstitution. Source: Department of Education’s Enrollment in Teacher Preparation Programs, Informational Paper.Available at: https://title2.ed.gov/.

21Estimating the number of students who complete a TPP once they have been admitted is difficult, as it requires adataset that tracks individual cohorts over time. A survey of seven TPP providers in the Milwaukee Metropolitan Areasuggests that roughly 80-90% of students who begin a TPP complete it (Yeado, 2016).

22IPEDS uses six-digit CIP codes for organizing academic programs. The first two digits of a CIP code correspondto the broadest area of study (e.g., all majors under CIP 13 pertain to those within the education field. These majorsinclude those designed to prepare individuals to become teachers, but also other majors such as “Educational Assess-ment, Evaluation, and Research” and “Educational Administration and Supervision”). The next two digits in the codegroup majors within similar instructional content and within the broader area of study. For instance, all majors underthe 13.12 CIP code belong to “Teacher Education and Professional Development, Specific Levels and Methods.” Thelast two digits are unique to the specific major. As an example, CIP code 13.1202 corresponds to the major “Elemen-tary Education and Teaching.” The CIP codes used by Kraft et al. (2018) are the following: 13.01, 13.02, 13.03, 13.10,13.12, 13.13, 13.14, and 13.99.

23CIP codes 13.12 and 13.13.24CIP code 13.

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IPEDS additionally provides information on the total number of bachelor’s degrees awarded ateach institution. This allows me to compute the share of graduates in a given institution who wereawarded a teaching degree. Throughout the paper I use both the share of awarded teaching degreesand the total number of teaching degrees at each institution as the outcome variables of interest.

In order to examine heterogeneity in the impacts of Act 10 by institutional quality, I collectan institution’s 2010-11 25th and 75th percentiles of freshman ACT composite scores as proxiesfor institutional selectivity.25 IPEDS does not report an institution’s average freshman ACT score.Instead, it reports only the 25th and 75th percentiles of an institution’s ACT score distribution.While work attempting to link observable characteristics at the time of hire to future teacher per-formance is still ongoing (Jacob et al., 2018; Rothstein, 2015), proxies for the selectivity of anindividual’s undergraduate institution have been widely used in the literature and have been shownto be correlated with future teaching performance (Kraft et al., 2018; Jacob et al., 2018; Angristand Guryan, 2008; Hoxby and Leigh, 2004; Figlio, 2002; Figlio and Rueben, 2001; Ehrenberg andBrewer, 1994).

To capture potential differences in teacher demand across states, I match the institution-leveldataset to time-varying, state-level covariates published by the NCES such as K-12 total state ap-propriations per pupil and student-teacher ratios. Furthermore, I estimate state-level teacher retire-ments from the Quarterly Workforce Indicators (QWI) as separations in elementary and secondaryeducation of people older than 55 years old (the minimum early retirement age for Wisconsin pub-lic school teachers). Finally, since teacher supply may be related to overall labor market conditionsthrough changes in relative expected wages (Nagler et al., 2015), I collect state-level economic in-dicators such as each state’s unemployment rate and per-capita GDP from the Bureau of LaborStatistics (BLS) and the Bureau of Economic Analysis (BEA), respectively.26

The final sample contains a balanced panel of higher education institutions in Wisconsin and ineach of the control states for the years 2004-05 through 2016-17. I exclude from the final samplestates that experienced changes in the influence of their teachers’ unions at some point duringthe sample period.27 However, in Section 4.2 I show that the results are robust to this samplerestriction.

Columns 1 and 2 of Table 1 report the pre-Act 10 means and standard deviations (in paren-theses) of various observables separately for institutions in Wisconsin and those in the Midwest

25The results in the paper are robust to using the institution’s acceptance rate rather than freshman ACT scores as aproxy for quality.

26Per-capita GDP is reported in chained 2012 dollars.27While Wisconsin’s union reform was arguably the most dramatic both in terms of regulatory scope and political

upheaval around it, since 2010 seven other states have passed legislation that weakens teachers’ unions. Idaho, Iowa,and Tennessee restricted collective bargaining. West Virginia and Missouri passed right-to-work laws in the publicsector. Finally, Indiana and Michigan passed both a right-to-work law and restrictions on collective bargaining (Roth,2017).

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(excluding Wisconsin). The variables are averaged over the seven years preceding the enactmentof Act 10 (2004-05 through 2010-11). Column 3 reports the point estimates and robust standarderrors (in parentheses) of tests for equality of means.28

Overall, prior to the enactment of Act 10 the average Wisconsin institution had a similar FTEenrollment and number of awarded teaching degrees to that of the average Midwestern institution.Similarly, the institutions had no meaningful differences in institutional selectivity, as measuredby freshman ACT test scores. The balance in these measures reinforces that Wisconsin institutionsand those in the rest of the Midwest were similar prior to Act 10’s enactment. The differencesin state-level variables between Wisconsin and the average Midwestern state highlight the need tocontrol for these covariates in the empirical analysis if one wishes to isolate the supply responses ofprospective teachers. Wisconsin and the average Midwestern state had large statistical differencesin pre-Act 10 variables that attempt to capture overall teacher demand and economic conditions.

4.2 DID

In order to obtain an estimate of the causal impact of Act 10 on the supply of prospective teachers,I estimate Equation 1 separately for each of the three control groups. This specification comparesthe share of teaching degrees in Wisconsin institutions before and after Act 10 and relative toinstitutions in the control groups in a DID framework:

Yist = βAct10st +XistΘ+µi + τt + εist (1)

where Yist is either the share or the total number of bachelor’s degrees awarded in teaching at insti-tution i in state s at time t; Act10st is a dummy variable equal to 1 if the institution is in Wisconsinand the time period is after the enactment of Act 10 (2011-12 to 2016-17); Xist is a vector of vari-ous state- and institution-level covariates that attempt to capture institutional selectivity, state-levelteacher demand, and the state-level economic climate. The estimation also includes institution(µi) and year (τt) fixed effects. Here, institution fixed effects control flexibly for any time invari-ant institution-specific characteristics, while year fixed effects control for any time-varying shocksthat affect all institutions in the same way. The parameter of interest is β , which captures thechange in the share of teaching degrees in Wisconsin’s higher education institutions and relative toinstitutions in the given control group.

The identifying assumption of the model is that were it not for Act 10, then the share of awardedteaching degrees in Wisconsin institutions and in those in the control group would have evolved in

28Institution-level rates are weighted by the institution’s total number of awarded degrees. State-level rates such asthe state’s K-12 appropriation per pupil, student-teacher ratio, unemployment rate, and per-capita GDP are weightedby the state’s total population.

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a similar way. While this assumption is inherently untestable, two necessary conditions must bemet for the assumption to hold: (1) institutions in Wisconsin and in the control group are on paralleltrends in the share of awarded teaching degrees prior to Act 10; and (2) there are no differentialshocks (other than the enactment of Act 10) in the treatment period.

In the next section I show using an event study that the first condition is likely to hold. I focus onthe second necessary condition here. To the best of my knowledge, Act 32 is the only policy passedconcurrently with Act 10 that would pose a threat to my identification strategy. As mentioned inSection 2.2, Act 32 decreased school districts’ equalization aid and revenue limits in the 2011-12 academic year. I argue that any effect of Act 32 on the share of awarded teaching degreeswould only attenuate positive estimates of β . A reduction in state aid to school districts should,if anything, decrease both the quantity and the quality of individuals pursuing and completing ateaching degree. For instance, Figlio and Rueben (2001) show that a state-level reduction in schoolspending through tax limits significantly reduces the quality of entrants into a state’s teachingworkforce. Nevertheless, I next show that estimates of the effects of Act 10 are robust to theinclusion of state aid to school districts as a control variable.29

The baseline results from the estimation of Equation 1 are shown in Table 2. The table presentsestimates of β along with standard errors in parentheses and clustered at the institution level. Thetable shows the robustness of the estimates across each control group and three different specifica-tions. Each column presents estimates obtained when using a particular set of states as the controlgroup. In Columns 4 - 6, I add to the sample states with some kind of teachers’ union reformduring the sample period to show that the estimates are robust to their initial exclusion.

Panel (a) shows the estimates obtained when including only institution and year fixed effectsin the estimation. In Panel (b) I add time-varying institution-level covariates to the specification.As a final robustness check, in Panel (c) I add state-level covariates that attempt to capture teacherdemand, state-level changes to public education funding, and the state’s economic conditions. Inthe first row of each panel, I use as the dependent variable the share of all graduates in a giveninstitution who were awarded a teaching degree. In the second row I use the institution’s totalnumber of awarded teaching degrees instead and control for the total number of awarded degreeson the right hand side of the equation. All regressions in which the dependent variable is the shareof awarded teaching degrees are weighted by the institution’s total number of awarded degrees toaccount for the large heterogeneity in institution size.

Overall, the estimates are robust to the choice of specification and control group, and indicatethat Act 10 led to an increase in the share of awarded teaching degrees at Wisconsin institutionsof roughly 1.5 percentage points. This effect corresponds to an increase of approximately 20

29While all results shown in the paper control for state aid linearly, the results are additionally robust to controllingfor it flexibly using cubic splines. These results are available upon request.

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additional teaching degrees, or roughly a 20% increase relative to the average number of annualteaching degrees awarded at a given Wisconsin institution prior to Act 10.

4.3 Event Study

Using the number of graduates from university-based TPPs as an outcome variable presents diffi-culties in defining treatment timing. Theoretically, one may expect responses in major choice tobe relatively inelastic for older cohorts (e.g., juniors and seniors). These cohorts have presumablymade costly investments toward degree completion and may not respond to the new incentives in ameaningful way. It is likely that any effect of deunionization on major choice would be primarilydriven by younger cohorts (e.g., freshmen and sophomores). Therefore, the effect of the law maynot manifest in the data until three or four years after its passage. The estimates of β shown inTable 2 represent a weighted average of union reform effects by year. As a result, they provide noinformation about the dynamics of the effects of the law. To uncover these effects, I estimate thefollowing event study specification:

Yist = ∑j 6=−1

γ jD(t−2012 = j)+µi + τt +XistΘ+ εist (2)

where Yist , µi, τt , and Xist are defined as in Equation 1; D(t−2012 = j) is a dummy variable thatequals one when the institution is in Wisconsin and is j years from 2011-12, the academic yearfollowing the enactment of Act 10. I include six leads and five lags of the treatment effect so thatγ j represents the coefficient on the jth lead or lag, and I omit the year prior to treatment so thatall estimates are relative to this year. This specification is attractive for two main reasons. First,a test for the parallel trends assumption is that γ j = 0 for all j < 0. Rather than controlling fordifferential pre-law trends across Wisconsin and the control group, this specification tests directlyfor the existence of such differentials in a fully flexible way. Second, this model allows for γ j,j > 0 to differ by year. This allows me to describe the dynamics of the impacts of Act 10 on theshare of individuals graduating with a teaching degree without assuming particular cohorts weremore or less affected by the law.

Figure 5 displays the results of the estimation of Equation 2. The figure presents point estimatesand 95% confidence intervals of the γ j’s for each period leading to and immediately after treatment.Panel (a) presents the estimates obtained when using border states as a control group, while Panels(b) and (c) show the results obtained when using division and Midwestern states instead. In allspecifications, the share of all graduates in a given institution who were awarded a teaching degreeis the outcome variable.

Prior to the enactment of Act 10, all treatment estimates are statistically insignificant at the

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5% level. This suggests that institutions in Wisconsin and those in the control groups had similartrajectories in the share of teaching degrees prior to the union reform. As expected, there appearsto be a lag in the effect of Act 10 on the share of teaching degrees in Wisconsin institutions. Theeffect of the law is small and statistically insignificant for the first two years after its enactment,which reflects the short-run inelastic responses of older cohorts of students.

When individuals who were in earlier years of their college careers at the time of Act 10’senactment and who had more time to respond to the increase in compensation and the enactmentof performance-pay schemes begin to graduate, the effects of Act 10 become larger and statisticallysignificant. On average, the magnitude of the estimates closely resembles that obtained from theestimation of Equation 1, and suggests that the Act led to an increase in the share of awardedteaching degrees at Wisconsin institutions of roughly 1.5 percentage points.

4.4 Heterogeneity by Institutional Quality

All else equal, students assigned to high-quality teachers are more likely than students assigned tolow-quality teachers to go to college and attain higher earnings (Chetty et al., 2014b). Therefore,while an analysis of the impact of teacher deunionization on the number of prospective teachersis important due to the current wave of teacher shortages throughout the U.S., the question offirst-order importance is how deunionization impacts the quality of the teacher pipeline.

To shed light on this question, I examine heterogeneity in the effects of Act 10 by institutionalselectivity. Specifically, I estimate Equation 3 separately for each of the three control groups:

Yist = βAct10st +δ (Act10st×ACTis)+XistΘ+µi + τt +νist (3)

where Yist , µi, τt , and Xist are defined as in Equation 1; ACTis is either the institution’s 2010-1125th or 75th percentile of freshman ACT scores.30 IPEDS does not report an institution’s averagefreshman ACT score. Instead, it reports only the 25th and 75th percentiles of an institution’s ACTscore distribution. While the results are very similar using either percentile, throughout this sectionI present estimates of Equation 3 separately for each measure. I standardize both the 25th and the75th percentile scores to a mean of zero and a standard deviation of 1 using the distribution ofscores of the relevant control group. For instance, when estimating Equation 3 using Midwesternstates as the control group, I standardize the scores using the distribution of scores of institutionsin the Midwest.

In this specification the effect of Act 10 on the institution’s share of teaching degrees dependson ACTis linearly and is represented by the expression β +δACTis. Therefore, β measures the im-

30The results are robust to choosing other pre-Act 10 ACT reporting years. They are additionally robust to usingthe institution’s acceptance rate rather than freshman ACT scores as a proxy for quality.

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pact of Act 10 at institutions with an ACT score in the middle of the distribution. δ measures howthe effect of Act 10 changes with institutional selectivity. A positive estimate of δ indicates thatthe effect of Act 10 on new teacher supply is more positive for institutions with higher freshmanACT scores.

Table 3 presents estimates of β and δ separately for each control group. The first three columnspresent the estimates obtained when using an institution’s 25th percentile of freshman ACT scores,while the last three columns show the results obtained when using the 75th percentile instead.All estimates of δ are positive and statistically significant, indicating that institutions with higherfreshman ACT scores experienced relatively larger increases in the share of teaching degrees as aresult of Act 10.

Figures 6 and 7 plot estimates of β +δACTis for a range of values of ACTis and separately foreach control group. The figures trace out estimates of the effect of Act 10 on the share of awardedteaching degrees, β + δACTis, for values of ACTis between three standard deviations below andabove the mean. For instance, the leftmost point of the line shows estimates of β −3δ , the effectof Act 10 on the share of awarded teaching degrees at institutions with freshman ACT scores ofthree standard deviations below the mean. The solid line traces out the point estimates while thedashed line delineates the corresponding 95% confidence intervals.

The results in the figures show that the increase in the share of teaching degrees brought aboutby Act 10 was entirely driven by relatively more selective institutions. For instance, using anycontrol group, the figures provide no evidence that institutions with a less-than-average pre-reformACT score experienced a change in the share of teaching degrees as a result of the reform. Whilemost of the coefficient estimates are negative, they are not statistically significant. However, thefigures show that institutions with freshman ACT scores of one or more standard deviations abovethe mean experienced increases in the share of teaching degrees of roughly 2 percentage points.

A caveat of these results, however, is that the specification in Equation 3 assumes the effect ofAct 10 is linear in ACTis. To relax this assumption, I complement the analysis by estimating thefollowing equation:

Yist =β1Act10st +β2(Act10st×Q2is)+β3(Act10st×Q3is)+ (4)

β4(Act10st×Q4is)+XistΘ+µi + τt +νist

where Yist , µi, τt , Xist , and ACTis are defined as in Equation 3; Q2,Q3,Q4 are dummy variablesindicating which quartile of the distribution of 2010-11 ACT composite scores the institution isin. As with Equation 3, I estimate this specification separately for the 25th and 75th percentilescores and for each control group. Thus, when using the 25th percentile, Q2 is equal to 1 ifinstitution i is in the second quartile of the distribution of 25th percentile ACT scores. In this

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specification β1 measures the impact of Act 10 on the share of teaching degrees at the least selectiveinstitutions (those with an ACT score in the first quartile of the distribution). βi, i ∈ 2,3,4 capturesthe differential impact of Act 10 on the share of teaching degrees at institutions with ACT scoresin the ith quartile of the distribution (relative to those in the first quartile).

Panel (a) of Table 4 presents estimates of β1,β2,β3, and β4 separately for each control groupand using either the 25th or 75th percentile of ACT scores. In all specifications, β4 is positive andstatistically significant. These results indicate that the impact of Act 10 on the share of teachingdegrees is relatively more positive for the most selective institutions than for the least selectiveones.

Panel (b) presents estimates of linear combinations of the coefficients. These linear combina-tions reveal the average effect of Act 10 at institutions in different parts of the ACT score distribu-tion. For instance, the fourth row presents estimates of β1 +β4, the effect of Act 10 on the mostselective institutions. The estimates in Panel (b) indicate that the average effect of Act 10 on theshare of teaching degrees is entirely driven by institutions in the fourth quartile of the distribution.There is no evidence that Act 10 had an impact on the share of teaching degrees at less selectiveinstitutions. These results are consistent with those obtained from the estimation of Equation 3.

Altogether, the results in this section suggest that the individuals who selected into a teachingmajor under the new Act 10 incentives were those at relatively more selective institutions. Theseresults are suggestive of an increase in the quality of the prospective teacher pool in Wisconsinas a result of Act 10. The estimates also suggest that the increase in compensation for high-quality teachers, as well as the departure from salary schedules that over-compensate low-qualityteachers and under-compensate high-quality ones, outweighed the increase in risk associated withdeunionization and incentivized high-quality individuals to select into the teaching profession.

5 Conclusion

Despite the pervasive debate surrounding teachers’ unions and their impacts on teacher recruit-ment, the causal effect of unions on new teacher supply has not been rigorously examined due to alack of variation in public sector unionism. Exploiting recent variation in union strength inducedby the enactment of Wisconsin’s Act 10, a measure that severely reduced the influence of teach-ers’ unions in the state and gave school districts the freedom to redesign teacher compensationschemes, this study aims to fill this gap in the literature.

Comparing the quantity of individuals completing a teaching degree in Wisconsin institutionsbefore and after Act 10 and relative to those in similar states, I find that Act 10 led to a 20%increase in the number of awarded teaching degrees. This effect was entirely driven by the mostselective institutions, which suggests an increase in the quality of the prospective teacher pool in

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Wisconsin as a result of the union reform.A few words of caution are in order. First, using the number of graduates from university-based

TPPs is far from a perfect measure of new teacher supply. Not all graduates from TPPs seek toobtain a job in the public education system. Some may decide to teach in private schools or workoutside of the education sector altogether. Furthermore, even if graduates do wish to enter thepublic education system, they may seek to teach in a different state than the one in which theycompleted their preparation. Therefore, while my results suggest that the quantity of individualsgraduating from Wisconsin institutions with a teaching degree increased as a result of Act 10, theydo not necessarily imply that the quantity of new teachers in the state increased as well.

Second, teacher quality is subjective and unobservable. Even though proxies for teacher qualitysuch as the selectivity of an individual’s undergraduate institution have been widely used in theliterature and have been shown to be correlated with future teacher effectiveness, they are imperfectmeasures. The literature has yet to reach a consensus regarding which traits of individuals at thetime of hire fully capture future teacher quality. The findings in this study regarding the impacts ofdeunionization on the quality of prospective new teachers should thus be interpreted with caution.

Finally, one should keep in mind the external validity of the results. Wisconsin’s Act 10 haspossibly been the most dramatic example of a reduction in the influence of teachers’ unions bothin terms of its regulatory scope and the political upheaval surrounding it. The results in the papercould partially reflect changes in the perception of the teaching profession due to the politicaldiscourse surrounding Act 10, rather than changes in the structure of the teacher labor market.The estimates presented in the study are most generalizable to states with a similar pre-reformregulatory environment to Wisconsin, and to policies that resemble Act 10 both in terms of theircontent and subsequent political upheaval.

With these weaknesses in mind, the present study has important policy implications. Thefindings of this and other recent studies have begun to provide a clearer understanding of the effectsof teacher deunionization on both the labor market for teachers and student outcomes. Similar tothe findings of Biasi (2018) for incumbent teachers in Wisconsin, the results here indicate that newhigh-quality individuals can be lured into school districts with compensation schemes that rewardperformance rather than seniority and educational attainment alone.

Understanding whether the increase in the quality of prospective new teachers as a result ofthe union reform translates into improvements in student outcomes in Wisconsin is an importantquestion for future research. While Baron (2018) shows that Act 10 led to a decrease in studenttest scores in the short run, an analysis of the long-run effects that arise after Act 10’s initial shockremains to be done. The present study provides evidence that the general equilibrium effects ofAct 10 on student outcomes, which will depend on its effect on the supply of new teachers, mightdiffer substantially from its short-run disruptive effects.

22

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26

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Figure 1: Effects of Act 10 on Wisconsin’s Union Membership

020

4060

Per

cent

of W

orke

rs in

Uni

ons

1980 1990 2000 2010 2020Year

Public Sector − WI Public Sector − Rest of USPrivate Sector − WI Private Sector − Rest of US

Figure shows the dramatic decline in public sector union membership in Wisconsin following the enactment of Act10 in 2011. Roughly half of public sector employees in Wisconsin belonged to a union prior to 2011, well abovethe national average of 35%. Between 2011 and 2012, Wisconsin’s public sector union membership decreased from50% to 37% and continued to plummet in the following years to approximately 22% in 2016. In contrast, the nationalaverage remained roughly constant at 35% (Hirsch and Macpherson, 2017).

27

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Figure 2: Changes in the Teaching Profession Around Act 10

(a) Teacher Retirements

.025

.035

.045

.055

.065

Sha

re o

f Tea

cher

s R

etiri

ng

2006 2007 2008 2009 2010 2011 2012 2013 2014 2015Fiscal Year

(b) Teacher Compensation

1000

015

000

2000

025

000

3000

035

000

Am

ount

in D

olla

rs

2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016Fiscal Year

Average Salary Average Fringe BenefitsAverage Compensation

(c) Teacher Compensation by Experience

2500

030

000

3500

040

000

Am

ount

in D

olla

rs

2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016Fiscal Year

0− 5 Years 5−10 Years10−20 Years 20−30 Years

(d) Interdistrict Teacher Transfers

.01

.015

.02

.025

.03

Sha

re o

f Tea

cher

s M

ovin

g D

istr

icts

2007 2008 2009 2010 2011 2012 2013 2014 2015Fiscal Year

Figure presents the time series of the share of teacher retirements, the share of interdistrict teacher transfers, averageteacher compensation and teacher compensation by experience level in Wisconsin’s public school districts before andafter 2011-12, the academic year following the enactment of Act 10. Data come from the WDPI. I follow Roth (2017)and estimate the teacher retirement rate as the attrition rate for retirement-eligible teachers - those older than 55 yearsold, the minimum early retirement age for Wisconsin public school teachers. Thus, the retirement rate in year t iscomputed as the fraction of total teachers in Wisconsin in year t who are eligible to retire and leave the sample in yeart + 1. The teacher turnover rate in year t is computed as the proportion of all teachers who in year t transferred to anew public school district. When computing aggregate variables from the individual-level dataset, I weight teachersby their corresponding FTE units. Total salary and fringe benefits are converted to real dollars using 1982-84 as thebase period.

28

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Figure 3: Sets of Control States

LegendBorder StatesDivision StatesMidwestern States

Figure shows the three distinct sets of nearby states that I use throughout the paper as control groups. The first controlgroup is border states (IL, IA, MI, and MN). The second control group consists of states in the East North CentralDivision (IL, IN, MI, and OH). Finally, states in the Midwest Region (IL, IN, MI, OH, MN, IA, MO, ND, SD, NE,and KS) comprise the third control group.

29

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Figure 4: State-Level Enrollment in TPPs

(a) Border States

1.5

22.

53

3.5

4S

hare

in T

PP

s

2009 2010 2011 2012 2013 2014 2015 2016Fiscal Year

Wisconsin Control Group

(b) Division States

1.5

22.

53

3.5

4S

hare

in T

PP

s

2009 2010 2011 2012 2013 2014 2015 2016Fiscal Year

Wisconsin Control Group

(c) Midwest States

1.5

22.

53

3.5

4S

hare

in T

PP

s

2009 2010 2011 2012 2013 2014 2015 2016Fiscal Year

Wisconsin Control Group

The figure shows trends in the share of postsecondary students who are enrolled in a TPP in Wisconsin before andafter Act 10 and relative to the three control groups. Information on the number of students who have been admittedto a TPP comes from the Department of Education (DOE) and is available from 2008-09 through 2015-16. State-levelenrollment in postsecondary education is published annually by the National Center for Education Statistics (NCES).

30

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Figure 5: Event Study

(a) Border States

-3-2

-10

12

3C

hang

e in

Sha

re o

f Tea

chin

g D

egre

es

t-7 t-6t-6 t-5 t-4 t-3 t-2 t-1 t t+1 t+2 t+3 t+4 t+5Time to Treatment

(b) Division States

-3-2

-10

12

3C

hang

e in

Sha

re o

f Tea

chin

g D

egre

es

t-7 t-6t-6 t-5 t-4 t-3 t-2 t-1 t t+1 t+2 t+3 t+4 t+5Time to Treatment

(c) Midwest States

-3-2

-10

12

3C

hang

e in

Sha

re o

f Tea

chin

g D

egre

es

t-7 t-6t-6 t-5 t-4 t-3 t-2 t-1 t t+1 t+2 t+3 t+4 t+5Time to Treatment

Figures present point estimates and 95% confidence intervals of the γ j’s for each period leading to and immediatelyafter treatment. The year prior to treatment is omitted so that all estimates are relative to this year. The model isestimated separately for each of the three control groups. Standard errors used in the construction of the confidenceintervals are clustered at the institution level. All specifications are weighted by the institution’s total number ofawarded degrees.

31

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Figure 6: Heterogeneity by Quality (ACT 25th Percentile)

(a) Border States

-4-2

02

4C

hang

e in

Sha

re o

f Tea

chin

g D

egre

es

-3 -2 -1 0 1 2 3Pre-Reform ACT Score

(b) Division States

-4-2

02

4C

hang

e in

Sha

re o

f Tea

chin

g D

egre

es

-3 -2 -1 0 1 2 3Pre-Reform ACT Score

(c) Midwest States

-4-2

02

4C

hang

e in

Sha

re o

f Tea

chin

g D

egre

es

-3 -2 -1 0 1 2 3Pre-Reform ACT Score

The figure plots estimates of β + δACTis obtained from the estimation of Equation 3 for distinct values of ACTis andseparately for each control group. I perform a z-score transformation of the scores to aid interpretation of the results.The figure traces out estimates of the effect of Act 10 on the share of awarded teaching degrees, β +δACTis, for valuesof ACTis between three standard deviations below and above the mean. As an example, the leftmost point of the lineshows estimates of β − 3δ , the effect of Act 10 on the share of awarded teaching degrees at institutions with 25thpercentile ACT scores that are three standard deviations below the mean. The solid line traces out the point estimateswhile the dashed line delineates the corresponding 95% confidence intervals. All specifications are weighted by theinstitution’s total number of awarded degrees. Standard errors used in the construction of the confidence intervals areclustered at the institution level.

32

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Figure 7: Heterogeneity by Quality (ACT 75th Percentile)

(a) Border States

-20

24

Cha

nge

in S

hare

of T

each

ing

Deg

rees

-3 -2 -1 0 1 2 3Pre-Reform ACT Score

(b) Division States

-20

24

Cha

nge

in S

hare

of T

each

ing

Deg

rees

-3 -2 -1 0 1 2 3Pre-Reform ACT Score

(c) Midwest States

-4-2

02

4C

hang

e in

Sha

re o

f Tea

chin

g D

egre

es

-3 -2 -1 0 1 2 3Pre-Reform ACT Score

The figure plots estimates of β + δACTis obtained from the estimation of Equation 3 for distinct values of ACTis andseparately for each control group. I perform a z-score transformation of the scores to aid interpretation of the results.The figure traces out estimates of the effect of Act 10 on the share of awarded teaching degrees, β +δACTis, for valuesof ACTis between three standard deviations below and above the mean. As an example, the leftmost point of the lineshows estimates of β − 3δ , the effect of Act 10 on the share of awarded teaching degrees at institutions with 75thpercentile ACT scores that are three standard deviations below the mean. The solid line traces out the point estimateswhile the dashed line delineates the corresponding 95% confidence intervals. All specifications are weighted by theinstitution’s total number of awarded degrees. Standard errors used in the construction of the confidence intervals areclustered at the institution level.

33

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Table 1: Pre-Act 10 Summary Statistics

Midwest Wisconsin Differences

Institution-Level VariablesDependent VariablesShare of Teaching Degrees 10.16 8.20 1.96∗∗∗

(7.74) (5.03) (0.68)Number of Teaching Degrees 104.66 97.87 6.79

(144.41) (88.73) (7.52)Institution FeaturesNumber of Total Degrees 1,030.07 1,193.62 -163.55

(1,436.64) (1,521.35) (113.63)Total FTE Enrollment 5,777.48 6,179.91 -402.43

(8,466.68) (7,322.24) (566.53)ACT 25th Percentile 21.75 21.73 0.02

(2.94) (2.84) (0.43)ACT 75th Percentile 26.70 26.23 0.47

(2.63) (2.55) (0.38)Acceptance Rate 72.20 77.35 -5.16∗∗∗

(13.08) (11.36) (1.45)State-Level VariablesEducation System FeaturesState Aid per Pupil ($) 4,871.16 5,785.83 -914.66∗∗∗

(1,441.10) (195.42) (46.78)Student-Teacher Ratio 15.64 14.76 0.89∗∗∗

(0.74) (0.25) (0.03)Number of Teacher Retirements 24,730.54 18,002.86 6,727.68∗∗∗

(13,159.21) (1,472.92) (411.06)Economic ConditionsUnemployment Rate 7.07 6.34 0.74∗∗∗

(2.27) (1.76) (0.15)Per-Capita GDP ($) 51,224.98 46,994.83 4,230.16∗∗∗

(4,151.62) (787.58) (158.56)

Columns 1 and 2 report the pre-Act 10 means and standard deviations (in parentheses) of various observablesseparately for institutions in Wisconsin and those in the average Midwestern state (excluding Wisconsin). Column 3reports the point estimates and robust standard errors (in parentheses) of tests for equality of means. Institution-levelrates are weighted by the institution’s total number of awarded degrees. State-level rates such as the state’s aid perpupil, student-teacher ratio, unemployment rate, and per-capita GDP are weighted by the state’s total population.Per-capita GDP is reported in chained 2012 dollars.∗ p < 0.10, ∗∗ p < 0.05, ∗∗∗ p < 0.01

34

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Tabl

e2:

Est

imat

esof

Equ

atio

n1

Exc

ludi

ngR

efor

mSt

ates

Incl

udin

gR

efor

mSt

ates

(1)

(2)

(3)

(4)

(5)

(6)

Pane

l(a)

:Ins

titut

ion

and

Year

Fixe

dE

ffec

tsSh

are

ofTe

achi

ngD

egre

es1.

203∗∗

1.17

9∗∗

0.69

21.

159∗∗

1.58

2∗∗∗

0.94

7∗∗

(0.6

03)

(0.5

39)

(0.4

47)

(0.5

75)

(0.5

47)

(0.4

38)

Num

bero

fTea

chin

gD

egre

es17

.120∗∗

20.1

99∗∗∗

8.41

7∗18

.920∗∗∗

24.2

70∗∗∗

11.3

62∗∗

(7.0

02)

(6.8

93)

(4.8

81)

(7.1

16)

(6.9

08)

(4.7

38)

Pane

l(b)

:Ins

titut

iona

lFea

ture

sSh

are

ofTe

achi

ngD

egre

es1.

362∗∗∗

1.42

3∗∗∗

0.84

0∗∗

1.33

0∗∗∗

1.74

6∗∗∗

1.05

5∗∗∗

(0.4

32)

(0.4

92)

(0.3

99)

(0.4

88)

(0.5

10)

(0.4

06)

Num

bero

fTea

chin

gD

egre

es17

.638∗∗

20.5

17∗∗∗

8.79

4∗19

.151∗∗∗

24.2

36∗∗∗

11.3

59∗∗

(7.0

09)

(7.0

13)

(4.9

66)

(7.2

29)

(6.9

36)

(4.7

86)

Pane

l(c)

:Sta

te-L

evel

Cov

aria

tes

Shar

eof

Teac

hing

Deg

rees

1.67

2∗∗∗

1.71

9∗∗∗

1.06

9∗∗∗

1.75

3∗∗∗

1.73

0∗∗∗

1.12

3∗∗∗

(0.4

35)

(0.4

54)

(0.3

71)

(0.4

51)

(0.4

04)

(0.3

52)

Num

bero

fTea

chin

gD

egre

es22

.641∗∗∗

24.9

46∗∗∗

12.8

01∗∗

27.5

26∗∗∗

26.0

67∗∗∗

13.3

66∗∗∗

(6.8

50)

(7.1

20)

(5.0

29)

(7.5

03)

(6.4

61)

(4.6

20)

Pre-

Ref

orm

Ave

rage

Shar

eof

Teac

hing

Deg

rees

inW

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208.

208.

208.

208.

208.

20Pr

e-R

efor

mA

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geN

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each

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Deg

rees

inW

I97

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797

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97.8

797

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97.8

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ontr

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720

05-1

720

05-1

720

05-1

720

05-1

720

05-1

7N

1,31

31,

456

2,41

82,

041

2,32

74,

017

Tabl

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tabl

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acro

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ree

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sa

final

robu

stne

ssch

eck,

inPa

nel(

c)Ia

ddst

ate-

leve

lcov

aria

tes

that

atte

mpt

toca

ptur

ete

ache

rdem

and,

stat

e-le

velc

hang

esto

publ

iced

ucat

ion

fund

ing,

and

the

stat

e’s

econ

omic

cond

ition

s.In

the

first

row

ofea

chpa

nel,

Iuse

asth

ede

pend

entv

aria

ble

the

shar

eof

allg

radu

ates

ina

give

nin

stitu

tion

who

wer

eaw

arde

da

teac

hing

degr

ee.I

nth

ese

cond

row

Iuse

the

inst

itutio

n’s

tota

lnum

bero

faw

arde

dte

achi

ngde

gree

sin

stea

dan

dco

ntro

lfor

the

tota

lnum

bero

faw

arde

dde

gree

son

the

righ

than

dsi

deof

the

equa

tion.

All

regr

essi

ons

inw

hich

the

depe

nden

tva

riab

leis

the

shar

eof

awar

ded

teac

hing

degr

ees

are

wei

ghte

dby

the

inst

itutio

n’s

tota

lnu

mbe

rof

awar

ded

degr

ees

toac

coun

tfor

the

larg

ehe

tero

gene

ityin

inst

itutio

nsi

ze.∗

p<

0.10

,∗∗

p<

0.05

,∗∗∗

p<

0.01

.

35

Page 37: Union Reform, Performance Pay, and New Teacher Supply: … · 2019-03-11 · Critics of teachers’ unions argue that unionized compensation schemes, known as salary sched- ules,

Table 3: Estimates of Equation 3

25th Percentile 75th Percentile(1) (2) (3) (4) (5) (6)

Independent Variable (Coefficient)Act10 (β ) 0.902 0.884∗ 0.363 1.061∗ 1.025∗∗ 0.547

(0.578) (0.511) (0.418) (0.564) (0.497) (0.395)Act10×ACT (δ ) 0.665∗∗∗ 0.701∗∗∗ 0.637∗∗∗ 0.658∗∗∗ 0.667∗∗∗ 0.604∗∗∗

(0.165) (0.174) (0.157) (0.183) (0.185) (0.167)Control Group Border Division Midwest Border Division Midwest

Years 2005-17 2005-17 2005-17 2005-17 2005-17 2005-17N 1,313 1,456 2,418 1,313 1,456 2,418

Table presents estimates of β and δ along with standard errors in parentheses and clustered at the institution level. Eachcolumn presents the estimates obtained when using a particular control group. The first three columns present estimatesobtained when using an institution’s 25th percentile of freshman ACT scores, while the last three columns show theresults of the estimation when using the 75th percentile instead. All estimates of δ are positive and statisticallysignificant, indicating that institutions with higher freshman ACT scores experienced relatively larger increases in theshare of teaching degrees as a result of Act 10. All specifications are weighted by the institution’s total number ofawarded degrees.∗ p < 0.10, ∗∗ p < 0.05, ∗∗∗ p < 0.01.

36

Page 38: Union Reform, Performance Pay, and New Teacher Supply: … · 2019-03-11 · Critics of teachers’ unions argue that unionized compensation schemes, known as salary sched- ules,

Tabl

e4:

Est

imat

esof

Equ

atio

n4

25th

Perc

entil

e75

thPe

rcen

tile

(1)

(2)

(3)

(4)

(5)

(6)

Pane

l(a)

:Ind

ivid

ualC

oeffi

cien

tsA

ct10

(β1)

0.50

30.

480

-0.0

100.

706

0.68

30.

198

(0.7

66)

(0.7

17)

(0.6

50)

(0.7

20)

(0.6

67)

(0.5

95)

Act

10×

Q2

(β2)

0.22

40.

222

0.22

00.

220

0.22

00.

215

(0.8

05)

(0.8

04)

(0.8

01)

(0.6

27)

(0.6

27)

(0.6

25)

Act

10×

Q3

(β3)

0.12

70.

125

0.12

20.

099

0.97

00.

095

(0.7

36)

(0.7

36)

(0.8

01)

(0.6

88)

(0.6

87)

(0.6

84)

Act

10×

Q4

(β4)

1.56

8∗∗∗

1.56

7∗∗∗

1.56

5∗∗∗

1.53

0∗∗∗

1.53

1∗∗∗

1.52

7∗∗∗

(0.5

91)

(0.5

92)

(0.5

89)

(0.5

24)

(0.5

24)

(0.5

22)

Pane

l(b)

:Eff

ects

ofA

ct10

byQ

uart

ileFi

rstQ

uart

ile(β

1)0.

503

0.48

0-0

.010

0.70

60.

683

0.19

8(0

.766

)(0

.717

)(0

.650

)(0

.720

)(0

.667

)(0

.595

)Se

cond

Qua

rtile

(β1+

β2)

0.72

70.

702

0.21

50.

927

0.90

30.

413

(0.7

59)

(0.7

08)

(0.6

40)

(0.6

26)

(0.5

66)

(0.4

77)

Thi

rdQ

uart

ile(β

1+

β3)

0.63

00.

125

0.11

70.

806

0.78

00.

293

(0.6

87)

(0.6

31)

(0.5

53)

(0.6

85)

(0.6

29)

(0.5

51)

Four

thQ

uart

ile(β

1+

β4)

2.07

1∗∗∗

2.04

8∗∗∗

1.56

0∗∗∗

2.23

6∗∗∗

2.21

4∗∗∗

1.72

5∗∗∗

(0.5

29)

(0.4

54)

(0.3

40)

(0.5

23)

(0.4

46)

(0.3

30)

Con

trol

Gro

upB

orde

rD

ivis

ion

Mid

wes

tB

orde

rD

ivis

ion

Mid

wes

tY

ears

2005

-17

2005

-17

2005

-17

2005

-17

2005

-17

2005

-17

N1,

313

1,45

62,

418

1,31

31,

456

2,41

8

Tabl

epr

esen

tsth

ere

sults

obta

ined

from

the

estim

atio

nof

Equ

atio

n4.

Pane

l(a)

pres

ents

estim

ates

ofβ

1,β

2,β

3,an

4.In

this

spec

ifica

tion,

β1

mea

sure

sth

eim

pact

ofA

ct10

onth

esh

are

ofte

achi

ngde

gree

sat

the

leas

tsel

ectiv

ein

stitu

tions

(tho

sew

itha

pre-

refo

rmA

CT

scor

ein

the

first

quar

tile

ofth

edi

stri

butio

n).β

i,i∈

2,3,

4ca

ptur

esth

edi

ffer

entia

lim

pact

ofA

ct10

onth

esh

are

ofte

achi

ngde

gree

sat

inst

itutio

nsw

ithA

CT

scor

esin

the

ithqu

artil

eof

the

dist

ribu

tion

(rel

ativ

eto

thos

ein

the

first

quar

tile)

.Pa

nel(

b)pr

esen

tses

timat

esof

linea

rco

mbi

natio

nsof

the

coef

ficie

nts.

The

selin

ear

com

bina

tions

reve

alth

eef

fect

ofA

ct10

onin

stitu

tions

indi

ffer

entp

arts

ofth

epr

e-re

form

AC

Tsc

ore

dist

ribu

tion.

For

inst

ance

,the

four

thro

wpr

esen

tses

timat

esof

β1+

β4,

the

effe

ctof

Act

10on

the

mos

tsel

ectiv

ein

stitu

tions

-tho

sein

the

four

thqu

artil

eof

the

AC

Tsc

ore

dist

ribu

tion.

All

spec

ifica

tions

are

wei

ghte

dby

the

inst

itutio

n’st

otal

num

bero

faw

arde

dde

gree

s.St

anda

rder

rors

are

clus

tere

dat

the

inst

itutio

nle

vel.

∗p<

0.10

,∗∗

p<

0.05

,∗∗∗

p<

0.01

.

37