Board Interlocks and Earnings Quality

Linna Shi

School of Management, Binghamton University

(607) 777-4640

lshi@binghamton.edu

Ravi Dharwadkar

Whitman School of Management, Syracuse University

(315) 443-3386

rdharwad@syr.edu

David Harris

Whitman School of Management, Syracuse University

(315) 443-3362

dgharris@syr.edu

Keywords: Financial accounting practices; Earnings quality; Board interlocks; Audit committee

interlocks; Contagion; Corporate governance.

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Board Interlocks and Earnings Quality

Abstract: We show that board interlocked firms’ accounting practices as reflected in earnings

quality are significantly correlated, and more so for audit committee interlocks. We also show that

these associations arise after interlock formation and cease after interlock dissolution, consistent

with the notion that information about accounting practices transfers between interlocked firms. It

has been said “the bad drives out the good” and notorious accounting regulations’ violations

suggest this may be a legitimate concern for accounting practice diffusion. While we find some

evidence consistent with good accounting practices being transferred, improving some interlocked

firm’s accounting quality, we find more consistent and more significant evidence that bad

accounting, like disease versus good health, is more contagious. Overall, we document preliminary

evidence about the importance of the social context for financial accounting practices and

recommend that future researchers consider both monitoring and social context factors

simultaneously to better understand firms’ financial accounting practices.

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Board Interlocks and Earnings Quality

1. Introduction

Corporate governance research has recognized that the board of a large public firm fulfills not only

a monitoring role but also provides important connections and expert advice to the firm (Ronen and Yaari

2010). While extensive research has investigated the board’s monitoring role by examining how board and

the audit committee characteristics (e.g., size, composition, multiple directorships, duality, board ownership,

professional experience, etc.) affect monitoring effectiveness (Ahmed and Duellman 2006; Klein 2002;

Vafeas 2005), less attention has been paid to why and when board connections become conduits of practices

resulting in similarities of accounting choices. A burgeoning stream of research based in social network

theory is well positioned to inform why and when board connections lead firms to imitate one another due to

information transfers via board interlocks (see Lieberman and Asaba (2006) for a detailed review). Social

network researchers have documented extensively the importance of information transfers through board

interlocks that enable firm imitation in diverse contexts including firm political expenditures (Mizruchi

1989), firm philanthropic activity (Galaskiewicz and Wasserman 1989), the spread of antitakeover

mechanisms such as poison pills (Davis 1991), and firm choices regarding mergers and acquisitions

(Haunschild 1993). Empirical work based in this stream of research provides sound evidence that many firm

choices are often embedded in a larger social context (Granovetter 1985). More recently, researchers have

focused not only on understanding how board interlocks may enable the diffusion of undesirable firm

practices such as stock options backdating (Bizjak et al. 2009) and earnings management (Chiu et al. 2010;

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Hirshleifer and Teoh 2009) but also on the spillover effects of reputational penalties in financial fraud

reporting (Kang 2008).

Despite the increasing evidence of information transfer through board interlocks, accounting research

on board and audit committees characteristics has predominantly focused on monitoring associated with

structural characteristics of individual firms’ boards and their audit committees and its influences on earnings

management, accounting conservatism, financial reporting, and voluntary disclosure quality (Ahmed and

Duellman 2006; Klein 2002; Vafeas 2005). Less attention has been paid to the similarity of firms’ accounting

choices due to information transfers through board interlocks, with Chiu, Teoh, and Tian (2010) being the

sole exception (hereafter referred to as CTT). CTT (2010) examine 118 firms with earnings restatements to

identify extreme cases of earnings management and find that board interlocks are associated with the

transmission of this behavior to what they term as “susceptible firms” during the period when earnings were

manipulated by what they term as “infected firms.” Furthermore, they show that there are both positive and

negative associations between susceptible firms and infected firms, in that interlocks with infected firms

increase the chance of bad behavior while interlocks with good firms decrease it, and the structural position

of the interlocked director (e.g., board chairperson or audit committee member) matters significantly. While

CCT (2010) find overall support for their contagion arguments in their very specific context, they do not find

an effect arising from changes in board interlocks. While their paper definitely focuses on identifiable

accounting manipulation, it examines only extreme situations (comparable to poison pill adoption or stock

options backdating) that may not be applicable to the broader population of firms and their more routine

accounting choices.

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Given the developments in social network research highlighting the role of board interlocks for

information transfer and the lack of empirical work using this approach in accounting research, the main

objective of this paper is to incorporate the implications of the social context by examining how board

interlocks and audit committee interlocks influence such connected firms’ accounting choices. In doing so,

we build on CTT (2010) by testing the theoretical implications of social network theory and board interlocks

in the broader context of accounting choices for a general population of firms, rather than focusing on the

more egregious behaviors of a small sample of offenders (i.e., those firms associated with restatements).

First, we assess whether firms sharing common directors, either through a board interlock or an

audit committee interlock, make similar accounting choices. We evaluate if the implications of board and

audit committee interlocks are different with respect to information transfers through interlocks. Specifically,

the structural proximity of audit committee members to the firms’ financial reporting processes is predicted

to enable an audit committee interlock to have a greater influence than a board interlock. While it is unlikely

that directors make specific accounting choices, it is likely that they set generalized standards and

expectations regarding acceptable levels of discretionary accounting. Their advice based on their personal

experiences at other firms in this regard, coupled with their structural proximity to firms’ financial reporting

processes is expected to facilitate accounting isomorphism.

Second, we explore two plausible explanations for interlocked firms’ accounting isomorphism: (1)

that the ex-ante similarity of interlocked firms causes them to select similar board members, thereby

producing a spurious association between their accounting choices without any ex-post information transfer

between the firms (the “firm-director matching” explanation); and (2) that interlocked firms’ accounting

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choices become more similar ex-post due to information transfer through the newly-formed interlock (the

“contagion” explanation). To disentangle these two effects, we examine how the associations between

interlocked firms’ accounting choices change when, (1) new audit committee interlocks are formed, and (2)

existing audit committee interlocks are dissolved. We focus on audit committee interlocks as they reflect the

strongest general associations between interlocked firms’ accounting choices. If ex-post information transfer

drives the general results, then interlocked firms’ accounting choices will become more similar after

interlock formation, and less so after their dissolution. If ex-ante firm similarity drives the general results,

then there will be no change in the association between firms’ accounting choices on account of these events.

To test the effects of new audit committee interlocks, we compare the association between firms’ accounting

choices in the year before the interlock was formed to those of the year after. For audit committee interlock

dissolution, we compare the association between firms’ accounting choices in the year after interlock

dissolution to those of the year before it. These assessments help us understand whether the interlocked firms

were similar to begin with versus the audit committee interlock driving the similarity of their accounting

choices.

Third, we examine whether information transfer is similar for good versus bad accounting choices.

As mentioned earlier, much of social network research on board interlocks has focused on adoption of

specific practices, many of which have purely negative implications (e.g., stock options backdating, earnings

restatements, etc.). Given the lack of variance in these practices, it has been hard to assess if “good” and “bad”

practices diffuse similarly through board interlocks. Hence, we explore if the “bad drives out the good,” by

examining the effects of negative and positive accounting choices.

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Finally, limited research has been in a position to examine whether information transfer is a

“two-way” or a “one-way” street. Current research has focused on the adoption of certain practices such as

backdating, where it would be impossible to assess the reciprocity of information transfers. By focusing on

more general accounting choices, we can examine the directions that information flows after the creation of

new audit committee interlocks and assess whether information transfers through board interlocks are

unidirectional or bidirectional.

We use two measures of firm’s accounting choices for all our tests: (1) the absolute value of

discretionary accruals as a proxy for management discretion; and (2) e-loadings that reflect the market’s

evaluations of those accounting choices. We find supportive results for both of these measures. For all tests

we use a continuous accounting choice variable which is the calculated value of the measure, and an

aggregated, decile ranked variable. In an ideal world where all statistical assumptions are met, the continuous

measure has the most statistical power, but the decile ranking is robust to a wide variety of violations of

statistical assumptions while giving up little power, and finding consistent results with both measures

provides additional support for the findings.

As discussed in Dechow et al. (2010) the absolute value of discretionary accruals is a good measure

of the accounting discretion reflected in a firm’s reported financial statements. Thus, our findings with this

variable directly examine how the exercise of accounting discretion increases or decreases based on the board

interlocks of the firm. E-loadings measure the market’s evaluation of the quality of a firm’s accounting

choices. Greater exercises of accounting discretion have repeatedly been shown to be associated with a wide

variety of substandard firm behaviors (Dechow et al. 2010) and, thus, with generally poorer quality

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accounting. Thus, it follows that consistent results between these two measures would be reflected in greater

exercises of accounting discretion being associated with poorer market evaluations.

Using a large sample from the 1999-2006 time period, as described in detail below, we find that

audit committee interlocks are positively associated with both accounting choice variables and similarly for

the continuous and decile measures of them. We find that the coefficients for audit committee interlocks are

significantly greater than those of board interlocks. These results hold even after we adjust for sample

selection biases using Heckman selection models to account for the endogenous determination of these

interlocks, as well as after deleting the subsample of firms reporting restatements, thereby increasing the

generalizability of our results compared to CTT (2010). We find no accounting association in the year prior to

interlock formation, but do find a significant association in the year after. Similarly, there exists a significant

association in the year prior to interlock dissolution, but no relation in the year after. These findings provide

support for the contagion argument and are contrary to the firm-director matching explanation. Our findings

also suggest that “good” accounting choices at the initial firm (i.e., the information source firm) are not

associated with “good” choices at the susceptible firm (i.e., the information recipient firm). However, “bad”

accounting choices at the initial firm are significantly associated with “bad” accounting choices at the

susceptible firm, indicating that information transfers are contingent on the earnings quality of the

interlocked firms and that information transfers influence accounting choices only under certain

circumstances. Finally, we find that accounting choices of both the initial firm and the susceptible firm are

affected by new audit committee interlock formation, indicating that information transfer is a two-way street.

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Our findings contribute to both accounting and social networks research in several ways. With regard to

accounting research, we highlight how board interlocks and audit committee interlocks enable accounting

isomorphism and also extend CTT (2010) which focuses on a precise, unambiguous earnings management

situation but does not find support for the board interlock arguments (i.e., firms in their sample that have a

migrated director or a newly hired tainted director are not associated with a higher likelihood of earnings

management). Our tests regarding the effects of creation and dissolution of audit committee interlocks as well

as our choice of general accounting quality measures make our results more generalizable, and our data

support our contagion arguments. In addition to building on CTT (2010), we identify why and when social

network context matters for earnings quality and show that the quality of the information being transmitted

influences the chances of it being passed on, though, unfortunately, it seems that worse practices transmit

more easily than good practices. As mentioned earlier, previous research has by and large focused on how

both corporate governance and firm characteristics influence accounting choices. By considering firms’

social networks we incorporate how inter-organizational information transfers may influence accounting

choices. In doing so, we highlight why and when private information flows through director interlocks

influence accounting choices over and above the effects of corporate governance, firm characteristics and

industry informational events.

From the social network research perspective, we highlight the implications of information transfers

through board and audit committee interlocks for a large sample of firms for fairly generic managerial

decisions. Previous research has focused on specific firm practices such as corporate political expenditures,

corporate philanthropy, adoption of poison pills, and corporate strategies for a small sample of firms, with the

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emphasis being on discrete choices and their diffusion within the sample under consideration. In contrast to

previous research, our paper not only shows that information transfer is associated with interlocks, but also

finds that it begins with interlock formation and ends with interlock dissolution, which distinguishes

information transfer effects from the possibility that similar firms merely make similar choices. Another

important contribution of our paper lies in evaluating the strength of information transfers from different

types of interlocks—in this case, that audit committee interlocks matter more than board interlocks. Previous

research in social networks has rarely accounted for such differences. Finally, our paper establishes the

reciprocal nature of information transfers that previous research on diffusion of poison pills or earnings

management contagion, that by their research design, were unable to identify.

2. Prior Literature

2.1 The monitoring role of the board and the audit committee and accounting choices

Extensive research in corporate governance has explored both board and audit committee

characteristics (e.g., size, composition, multiple directorships, duality, board ownership, professional

experience, etc.) and how they affect accounting choices (Ahmed and Duellman 2006; Klein 2002; Vafeas

2006). While most initial research focused on board characteristics in general, recently, more attention has

been paid to the audit committee as it is the key operating committee of the board of directors that is charged

with primary oversight of financial reporting, disclosure and auditor selection. In general, the streams of

research at the board and audit committee level often mirror each other. For example, initially researchers

assessed how board independence was associated with high-quality financial reporting and more recently,

research has focused on audit committee independence in ensuring high-quality financial reporting. Low

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levels of independence is cited as problematic in both instances, suggesting that low independence is

associated with fraudulent financial statements (Beasley 1996, Abbott et al. 2004), less support for an

external auditor in disputed settings (DeZoort and Salterio 1998), managing earnings through discretionary

accruals (Klein 2002, Bedard et al. 2004), artificially beating earnings benchmarks (Vafeas 2005), and

internal control problems (Krishnan 2005, Zhang et al. 2007).

Second, researchers have focused on the backgrounds (i.e., financial and accounting expertise) of audit

committee members in improving monitoring effectiveness. Similar to audit committee independence, the

level of audit committee expertise is associated with the occurrence of accounting fraud (Abbott et al. 2004),

accounting conservatism (Bedard et al. 2004, Krishnan and Visvanathan 2008), and internal control quality

(Krishnan 2005). Audit committee members’ backgrounds are predictive of their willingness to support an

external auditor in disputes with management (Knapp 1987, DeZoort and Salterio 2001). Audit committee

expertise can also improve management voluntary disclosure, both in frequency and in quality (Karamanou

and Vafeas 2005) and the market reacts favorably to the appointment of audit committee directors with

financial expertise (DeFond et al. 2005). In summary, both board and audit committee characteristics have

been examined from the monitoring perspective, but little attention has been paid to how board connections

influence accounting choices.

2.2. The information diffusion role of board interlocks and similarities of firm practices

Board interlocks occur when a director of one firm sits on the board of directors of another firm

(Mizruchi 1989). Board interlocks are very common; Davis (1991) states that, “the median (Fortune 500)

firm was tied to seven others, while a handful of extremely central firms had nearly 50 interlocks”. According

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to Haunschild (1993) board interlocks are a credible and low-cost channel for information transfers between

firms. Given the high prevalence of interlocks, it is not surprising that they constitute an important, credible

information diffusion mechanism.

However, most prior research focuses on the diffusion of practices in terms of binary outcomes. For

example, both Davis (1991) and Davis and Greve (1997) find that board interlocks increase firms’ adoptions

of anti-takeover defenses such as poison pills and golden parachutes. Similarly, Haunschild (1993) and Stuart

and Yim (2010) find that board interlocks affect corporate acquisition activity and that a director’s direct

exposure to a merger deal from another board affects the likelihood of his/her current firm also being an

acquisition target. Furthermore, Bizjak et al. (2009) find that the likelihood of backdating stock options can

be explained by the presence of interlocking directors with backdating experience in other firms. In sum,

while research has clearly established that board interlocks are important enablers of the diffusion of firm

practices, it has tended to ignore the differences between general board interlocks and board committee

interlocks, why and when information transfers through the interlocks influence firm practices, and whether

these information transfers are reciprocal in nature.

3. Hypotheses Development

Most corporate governance research in accounting has taken an under-socialized view of accounting

choices, focusing on how specific board and audit committee characteristics improve accounting choices. In

the process, it has largely ignored how firms are embedded in larger social contexts and the role of social and

informational resources in enabling the dissemination of business practices. As discussed above, research on

firm choices in other strategic, non-strategic, and financial domains finds that firms mimic the choices of

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other firms they are linked to by board interlocks (e.g., Mizruchi 1989; Davis 1991; Bijak, et al. 2010).

Interlocking directors possess information about the accounting choices of firms where they serve on boards,

which becomes an informational input into the accounting decisions of the other firms they advise. The fact

that they have experienced these practices first-hand may make other board members more comfortable with

accepting similar choices at the focal firm as direct communication and familiarity with the other firms’

practices helps partially resolve the ambiguity surrounding these choices. Therefore, to the extent that a board

member is exposed to accounting choices at one firm, he/she is able to promote the adoption of similar

choices by providing first-hand evidence about them at the other firms where he/she sits on the board.

Beyond merely being aware of the other firm’s accounting choices, the fact that a specific choice may have

been made while the interlocked director served that firm suggests that they may not only be more

knowledgeable regarding the choices, but also be more likely endorse these choices

While boards are generally charged with firm oversight, the audit committee is most closely connected

to the financial reporting process. Both the Blue Ribbon Committee and the SEC have identified the

importance of the audit committee’s monitoring role. While previous research indicates that effective

monitoring by the audit committee leads to fewer internal control problems, more conservative accounting,

less earnings management, fewer incidents of financial reporting fraud, and higher quality voluntary

disclosure (e.g., Beasley 1996, Carcello and Neal 2000, 2003, Klein 2002, Abbott et al. 2004, Bedard et al.

2004, Krishnan 2005, Karamanou and Vafeas 2005, Vafeas 2005, Zhang et al. 2007, Krishnan and

Visvanathan 2008), it has rarely examined how directors interlocked through audit committee membership

may be conduits of information and influence across firms. The audit committee’s proximity to the reporting

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process and its association with the external auditors (e.g. Knapp 1987, DeZoort and Salterio 1998, DeZoort

and Salterio 2001), makes it an even more important conduit for information transfers. Therefore, we expect

that interlocked board members serving on audit committees increase the level of information transfer such

that audit committee interlocks are more influential than board interlocks in enabling accounting

isomorphism.

H1a: Interlocked firms’ accounting choices are positively associated.

H1b: Interlocked firms’ accounting choices are more positively associated when an interlock is through

audit committee membership than through the board at large.

The association of interlocks with the similarity of firms’ accounting choices is consistent with the social

network theory of information transfer (Granovetter 1985). However, it is also possible that interlocked firms’

accounting choices being similar only reflects their ex-ante relation, i.e., that similar firms make similar

choices, in general, and, specifically, that firms with similar accounting tend to seek similar directors. In

order to assess whether interlocks actually facilitate information transfer, we identify two situations that

imply causal relations. First, we consider instances of interlock formation. If newly interlocked firms merely

exhibit ex-ante propensities to make similar accounting choices, then the formation of a new board interlock

should not be associated with changes in those choices. Alternatively, if interlocks facilitate the transmission

of accounting choice information from one firm to another, then it should increase the similarities of their

choices. We similarly consider instances of interlock dissolution. If interlocked firms have been making

similar accounting choices only because of overall firm similarities and not due to information transfers

through their interlocks, then they should not alter their accounting choices after dissolution of those board

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committee interlocks. If, however, interlocks facilitating information transfer is the main source of

interlocked firms’ accounting similarities, then those similarities should cease after interlock dissolution.

H2a: Firms’ accounting choices become more similar after audit committee interlocks between them are

formed.

H2b: Firms’ accounting choices become less similar after audit committee interlocks between them are

dissolved.

Most prior social network research has not examined whether information transfers through

interlocks are conditional on the qualities of the source of that information. Some researchers have examined

the interlock-facilitated diffusion for specific choices or practices such as poison pills (Davis 1991) and stock

options backdating (Bijak, et al. 2010). Others have focused on non-strategic choices such corporate

philanthropy, political contribution, TQM adoption, etc. (Mizruchi 1989, Galaskiewicz and Wasserman 1989)

which may be more susceptible to social network pressures as firms try to gain legitimacy in the institutional

environment (DiMaggio and Powell 1983). As we are focusing on accounting choices using earnings quality,

we can assess how variations in their quality at the initial firm affect the information transfer. Such

assessments cannot easily be made in the case of discrete choices (e.g., adopting poison pills) or discrete

events (e.g., restatements), nor in cases where the choice has ambiguous qualities (e.g., philanthropy). On the

one hand, it is likely that information transfer should occur similarly for high and low quality earnings. On

the other hand, it is more likely that transfers of poor quality earnings may be reflective of the bad driving out

the good, or that it is easier to incorporate information about bad choices as such choices tend to be

unbounded whereas good quality information has a clear upside limit at the point of its being as objective as

possible. Therefore, we hypothesize that this association will be stronger for interlocked firms with worse

quality accounting choices.

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H3: Earnings quality associations are stronger for poor earnings quality than for good.

Finally, most prior social network research on board interlocks has not been done in contexts that

allow for examining whether information transfers are reciprocal. For example, research on the diffusion of

poison pills and stock options backdating preclude the existence of reciprocal information transfers. If

information transfer is a two-way street, then firms from which a member comes as well as firms whose

board he/she joins may either, or both, should experience accounting changes in subsequent time periods.

This may depend on the quality of the accounting choices at both firms. Furthermore, it is more likely that we

will be able to assess the two-way transfer in the context of accounting choices that are subject to

management discretion, than in contexts such as stock options backdating or poison pill diffusion.

H4: On formation of an audit committee board interlock, both firms’ accounting choices are affected

reciprocally.

4. Sample Selection

We limit our primary sample to all S&P 1500 firms from 1999 to 2006 that appear in Risk Metrics1. We

identify an initial sample of 12,611 firm-years and 118,753 firm-year-director observations. After merging

this dataset with COMPUSTAT, we retain 11,903 firm-year and 111,895 firm-year-director observations.

From these observations, we select all firms that have director(s) holding positions on board(s) of other S&P

firm(s)2, resulting in 8,212 firm-year observations and 39,807 firm-firm-year interlock observations

3. While

1 Audit committee information is not available prior to 1999.

2 It is possible that a firm has an interlock with a non-S&P firm, but we are not able to analyze a case due to data

availability for the non S&P firm.

3 When the same firm-firm interlock link exists through different directors, we count it as one interlock rather than

several interlocks.

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all firms in our sample have interlocks, we distinctly separate the interlocks into board interlocks and audit

committee interlocks. Specifically, we define an interlock link through a director who does not serve on a

firm’s audit committee as a “board interlock” and an interlock link through an audit committee member as an

“audit committee interlock”. Both variables are set equal to one when the condition is met and equal to zero

otherwise. In our sample, we have 16,861 firm-firm-year audit committee interlock observations and the

balance is board interlocks.4 We limit our sample to firms with at least one interlock link to better isolate the

information transfer effects. In our sample, a firm on average has 6.4 interlocks with other firms. Detailed

description about sample formation is summarized in Table 1.

5. Methodology

5.1 Tests of contagion effects on earnings quality

In order to test the overall contagion effects of board and audit committee interlocks, we start by

examining the general association between earnings quality of the paired interlocking firms and compare the

effects of board interlocks and audit committee interlocks. We run the following OLS regression with year

and industry fixed effects:5

∑ (1)

4 If an interlock link is through both audit committee member(s) and other director(s), we count it as one audit committee

interlock.

5 In untabulated results we also estimate a model that computes the association between all firms’ earnings qualities and

determines whether the association between interlocked firms’ earnings qualities is significantly greater. We find no

association for non-interlocked firms’ earnings qualities and a significantly greater association for interlocked firms’

earnings qualities, consistent with the results reported in the paper.

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where is the earnings quality of the information recipient firm in year t+1; is the earnings

quality of the information sending firm in year t; and are the control variables that might affect the

earnings quality.

In order to avoid the double counting problem, we randomly assign “information recipient firm” and

“information sending firm” in each pair of interlocking firms.6 This design assumes that information flows

through interlocks are temporally unidimensional (i.e., information cannot travel back in time). We utilize

lagged values because they fit well the temporal sequence of events that, first, the information sending firm

develops information about accounting choices which will affect its earnings quality, and, second, that

information is transferred by the interlocked director to the information recipient firm, which then considers

it and, possibly, acts on it. Thus, lagged values may better fit the data generating process than

contemporaneous values, but, which could also be descriptive if the process were sufficiently rapid.

Furthermore, we explore two plausible explanations for interlocked firms’ accounting isomorphism: (1)

that the ex-ante similarity of interlocked firms causes them to select similar board members, thereby

producing a spurious association between their earnings qualities without any ex-post information transfer

between the firms (the firm-director matching explanation); and (2) that interlocked firms’ accounting

choices become more similar ex-post due to information transfer through the newly-formed interlock (the

contagion explanation). To disentangle these two effects, we examine how the associations between

interlocked firms’ earnings qualities change when, (1) new audit committee interlocks are formed, and (2)

6 We also switch the receiving and sending status of each firm in an interlock and get very similar results.

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existing audit committee interlocks are dissolved. Specifically, we run the following regression for the two

scenarios and examine the association before and after such events:

∑

(2)

where all the variables are defined the same as in regression (1). Note that for the new interlock creation event,

we define firms whose existing directors start to serve on another board as the “information sending firms”

and the counterparts as the “information recipient firms”. For the old interlock dissolution event, we define

firms whose interlocking directors still serve on boards as the “information sending firms” and the

counterparts as the “information recipient firms”.

If the interlocked firms share some common characteristics and thus have similar earnings quality, we

expect to be significant both before and after the new interlock formation and the old interlock

dissolution. In contrast, if the information recipient firm’s earnings quality is affected only by the audit

committee interlocks, then, we should observe a significant only after the interlock has been formed, and

before the interlock is dissolved, and should be insignificant during the years before the interlock has been

formed or after the interlock is dissolved.

Next, we examine whether information transfer is symmetric for good versus bad accounting choices.

We explore whether the “bad drives out the good,” by examining the effects of negative and positive earnings

qualities. Specifically, we use the following two Probit regressions:

∑

(3)

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∑

(4)

where ( ) is an indicator variable equal to one if the earnings quality variable (i.e.

|DACC| and ELOADING) of the information recipient firm in year t+1 is in the lowest (highest) quintile and

zero otherwise; ( ) is an indicator variable equal to one if the earnings quality variable of the

information sending firm in year t is in the lowest (highest) quintile and zero otherwise; are the

control variables from regression (1).

Finally, we examine if information flows in both directions between the interlocked firms, using the

formation of new audit committee interlocks described earlier, and revisit the question of the differential

information transmission of good versus bad earnings quality. We test how information recipient firms’

earnings qualities are affected by the information sending firms with better or worse earnings qualities and

how information sending firms’ earnings qualities are affected subsequently. Specifically, we use the

following two regression models7:

(5)

(6)

where is the change in earnings quality one year after minus one year before the formation of a new

audit committee interlock; is an indicator variable equal to one with worse earnings quality firm

and equal to zero otherwise; is an indicator variable equal to is an indicator variable equal to

one with better earnings quality firm and equal to zero otherwise.

7 Both of the equations have no intercept.

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5.2 Measurement of earnings quality

We use two measures of earnings quality: the absolute value of discretionary accruals (|DACC|) and a

return-based representation of earnings quality, e-loading. Finding similar results with |DACC| and e-loading

is substantial support for our findings as it would evidence that the board’s oversight does affect

management’s exercise of accounting discretion, that interlocks do transfer information between firms about

such exercises of accounting discretion, and that the market finds financial statements that are subject to

greater amounts discretion to be of lower quality.

|DACC| has been commonly used in accounting literature to measure earnings management and earnings

quality (e.g. Dechow and Dichev (2002), Frankel et al. (2002), Chung and Kallapur (2003), Myers et al.

(2003), Leuz et al. (2003), Bergstresser and Philippon (2006). Specifically, Dechow et al. (2010) make the

point that |DACC|s, although may be more or less associated with the quality of firms’ performance and their

underlying values in different situations, are the most direct measure of the amount of discretion exercised by

management in the preparation of their financial reports. Thus, we investigate how management’s exercise of

accounting discretion will be affected by information transfers via board interlocks.

We first estimate discretionary accruals using the cross-sectional modified Jones (1991) model:

(

) ( ) (7)

where TACC is the total accruals calculated following Hribar and Collins (2002) as income before

extraordinary items (IBC) minus operation cash flows (OANCF) plus extraordinary items and discontinued

operations (XIDOC), scaled by average total assets; AVGAT is the average of the total assets at the beginning

and ending of the current year (AT); REV is the changes in sales (SALE) from the previous year to the

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current year t, scaled by the average total assets; AR is the changes in accounts receivable (RECT) from the

previous year to the current year t, scaled by the average total assets; PPE is the gross property, plant, and

equipment (PPEGT), scaled by the average total assets. All the variables are from COMPUSTAT and are

winsorized at the bottom and top one percent in order to reduce the influence of outliers. We estimate

Equation (2) for each two-digit SIC code and year combination with at least eight observations using all the

firms in NYSE/AMEX/NASDAQ market. The residual, is DACC.

We also use e-loading (ELOADING) as a more direct measure of the market’s assessment of earnings

quality. Ecker et al. (2006) shows that e-loading captures investors’ perceptions of a firm’s earnings quality

and reflects earnings attributes such as, persistence, predictability, smoothness, value relevance, timeliness,

conservatism, and accrual quality.8

Following Ecker et al. (2006), we estimate e-loading using the following regression model:

( ) (8)

where t is an index for the number of trading days in year T; Rj,t is the firm j’s return on day t; RF,t is the

risk-free rate on day t; RM,t is the market return on day t; SMBt is the small-minus-big factor on day t; HMLt is

the high-minus-low book-to-market factor on day t; AQfactort is an accruals quality mimicking factor on day

t, which is the difference in equal-weighted portfolio returns from buying the highest AQ quintile of the firm

and selling the lowest AQ quintile of the firm; Rj,t is from the CRSP daily return database and the rest of the

8 Core et al. (2008) argue that accruals quality, used as the accruals quality mimicking factor in Ecker et al. (2006) is not

a priced risk factor and cannot explain predicted risk returns. But this argument does not prevent e-loading from being a

good proxy for earnings quality. For example, Ecker et al. (2006) shows that e-loading is highly correlated with all the

seven proxies of earnings quality.

22

variables are all from the AQfactor dataset.9 We estimate regression (8) using a 1-year window with at least

45 observations.10

5.3 Control variables

We include two sets of control variables that have been shown to be related to earnings quality. The first

set of control variables includes firms’ innate characteristics that may affect our two earnings quality

measures. Francis et al. (2004, 2005), Hribar and Nicolas (2007), Ecker et al. (2006) and Dechow et al. (2010)

find that |DACC| and e-loadings can be affected by characteristics such as size, leverage, growth, operational

volatility, performance, off-balance-sheet activities and non-financial measures of the firm’s abnormal

change. In addition, two firms’ accounting choices might be similar when they share the same auditor. All

variables in this group are calculated using data from COMPUSTAT.

Firm’s size (SIZE) is measured by the log of market value of equity, which is the product of market price

(PRCC) * share outstanding (CSHO). We expect SIZE to be negatively associated with earnings quality.

LEVERAGE is measured as long-term debt (DLTT) plus debt in current liabilities (DLC) over average total

assets (AT). The effects of LEVERAGE on earnings quality are uncertain. On one hand, leverage increases

management incentives to manipulate earnings due to the risk it induces for high-volatility income; on the

other hand, large debt holders, especially banks, can act as diligent monitors and limit earnings management.

9 We thank Frank Ecker, Jenifer Franics, Irene Kim, Per M. Olsson, and Katherine Schipper for generously sharing their

AQfactor dataset.

10 As shown by Ecker et al. (2006, page 754), e-loading can be reliably calculated over intervals as short as 45 trading

days

23

We measure growth by market-to-book ratio (M/B),11

the market value of equity divided by the book value

of equity (CEQ). Managers in high growth firms are more likely to manipulate earnings. To measure

operational volatility, we use sales volatility (SALE_VOL),12

the standard deviation of sales (SALE) over year

t-4 to year t. High operational volatility may lead to high accruals volatility, higher |DACC| and larger

e-loadings. We also include an indicator variable, LOSS, to capture the effect of poor performance. LOSS is

equal to one when earnings before extraordinary items (IB) are negative and zero otherwise. Managers are

more likely to manipulate earnings when firms perform poorly. We use an indicator variable LEASE, which is

equal to one if a firm has future operational lease obligations (the sum of MRC1-MRC5 is larger than zero)

and zero otherwise, to measure firm’s off-balance sheet activities. Dechow et al. (2010) find that the amounts

of off-balance sheet activities negatively affect firm’s earnings quality. We follow Brazel et al., (2009) and

use abnormal employee change (ABNEPLOYEE) for the non-financial measure of firm’s abnormal change.

Specially, ABNEPLOYEE is the numbers of employees (EMP) in year t minus the number in year t-1, scaled

by the number in year t-1, less total assets at year t minus that of year t-1, scaled by assets at year t-1. We

expect ABNEPLOYEE to be positively related to |DACC| and e-loading. Our last control variable in this

group is Auditor link, an indicator variable equal to one if the paired firms in an interlock share the same

auditor (AU) and zero otherwise. We expect two firms’ earnings quality to be more related if they share the

same auditor.

11 We also use sales growth, the difference of sales (SALE) in year t minus that in year t-1, scaled by sales of year t-1, as

an alternate measurement of growth. We continue to find consistent results.

12 We also use cash flows volatility, the standard deviation of cash flow from operation (ONACF) over year t-4 to year t,

as an alternate measurement of operational volatility. We continue to find consistent results.

24

The second group of control variables includes governance structure variables. Research (e.g., Ahmed

and Duellman 2006) shows that earnings quality could be affected by governance factors including presence

of anti-takeover defenses, CEO duality, board independence, institutional shareholdings, and the total

number of interlocks through directors. All the control variables from this group are calculated using data

from Risk Metrics or Thomson Financial database.

We use G-INDEX as in Gompers et al. (2003) to measure governance from the anti-takeover defense

perspective. Firms with higher G-INDEX (“dictatorship” firms) often have poorer earnings quality. We use

an indicator variable (DUALIITY) equal to one if a firm’s CEO is also the chairman of board and zero

otherwise to control for the effect of duality. When the CEO and Chairman is the same person, the CEO may

more easily manipulate earnings. We measure board independence by the percentage of independent

directors on the board (INDEPENDENCE). More independent directors on board will help improve earnings

quality. We include the total percentage of institutional shareholdings (INST SHARE) as institutional

shareholders are more sophisticated and can attenuate earnings management behavior. Last, we calculate the

total number of board interlocks (#BOARD) to control for the possibility that the total number of board links

might affect firm’s earnings quality.

6. Empirical Results

6.1 Descriptive statistics

Descriptive statistics for the key variables appear in Table 2. Of the 39,807 interlock observations,

22,946 interlocks (58 percent of the sample) are through directors who do not serve on audit committees and

the remaining 16,861 interlocks (42 percent of the sample) are through directors who serve on audit

25

committees. Moreover, in 7,829 cases, the paired interlocking firms (20 percent of the sample) use the same

external auditor.

The mean, median, and standard deviation of |DACC| for the information sending firms are 4 percent, 2

percent, and 5 percent respectively, while those for the information recipient firms are 4 percent, 2 percent

and 6 percent. The mean, median and standard deviation of ELOADING for the information sending firms

are-0.09, -0.13 and 0.39 respectively, while those for the information recipient firms are -0.08, -0.12, and

0.41. For both earnings quality variables, the distributions of the information sending firms and the

information recipient firms are similar. The average size of firms in the sample is $8,844 million. The average

leverage ratio is 24 percent and the average market-to-book ratio is 2.99. Around 18 percent of firms in the

sample reported a loss and 86 percent of firms have operational leases. The mean and median G-index are

both nine. For 81 percent of firms in the sample the CEO is also the Chairman. On average, independent

directors represent 69 percent of the board while institutional shareholders hold 72 percent of firms’

outstanding shares. In sum, the distributions of all the innate firm characteristics and governance structures

are consistent with previous literature.

Table 3 reports the correlations between the key variables. |DACC| and ELOADING are highly

correlated, both between the information sending firms and the information recipient firms and within as well.

All control variables have significant relations with earnings quality, as discussed above.

6.2 General evidence of the contagion effects

We report the OLS regression results for Regression (1) in Table 4. In the first and second column, we

report results for the |DACC| earnings quality variable. In the first column, we utilize the raw continuous

26

value of |DACC|. The coefficient on the information sending firm’s |DACC| for board interlock, β1, is not

significant at 0.10 level (p-value=0.808), while the coefficient for the audit committee interlock, β2, is 0.047,

highly significant (p-value=0.000). The F-test indicates that the coefficient for the board interlock is

significantly less than that for the audit committee interlock (p-value=0.000). In second column, labeled

“Decile ranking,” we report the regression results when we use the decile ranking for all non-indicator

variables. The coefficients for board interlock, β1, are not significant in any model. In contrast, the

coefficients for audit committee interlock, β2, are significant in both models and the F-tests indicate that the

difference between the two coefficients is significant for both.

In the third and fourth columns, we report the regression results with the ELOADING earnings quality

variable. In contrast to our findings with the |DACC|, the coefficients for board interlock, β1, are significant in

all models regardless of whether we use the raw values or the decile rankings and with or without control

variables. Also, the coefficients for audit committee interlock, β2, are always positive and significant and

always significantly greater than the coefficients for board interlock, β1.

The results in Table 4 suggest several things. First, interlocks via the audit committee have significant

information transfer effects on both the use of accounting discretion by management and on the market’s

assessment of overall earnings quality, which includes many firm informational characteristics in addition to

accruals quality. That the audit committee is more significant with respect to accounting discretion than the

overall board is not surprising given their closer connection to financial reporting. On the other hand, the

overall director interlocks are significantly related to the market’s evaluation of firms’ accounting quality,

suggesting that information transfers do take place at the board level in addition to transfers via audit

27

committee interlocks. However, they appear to flow from characteristics other than firms’ accounting

accruals choices. Finally, in all cases audit committee interlocks are more significantly related to earnings

quality, of all kinds, than are general board interlocks. This is a logical and supportive result in that the audit

committee has primary responsibility for oversight of firms’ financial reporting functions.

Because we find the contagious effects of earnings quality are more significantly related to audit

committee interlocks than board interlocks, we focus on audit committee interlocks hereafter for the balance

of analyses.

6. 3 Contagion explanation versus firm-director matching explanation

The general association between interlocked firms’ earnings qualities can be due to different reasons. In

this section, we address whether firms with ex-ante similar earnings qualities tend to have similar

propensities in selecting directors, the firm-director matching hypothesis, or whether firms’ accounting

choices and therefore earnings qualities, ex-post become more similar after retaining another firm’s director

due to information transfers, the contagion hypothesis. We evaluate the two competing hypotheses by

examining events around changes in audit committee interlocks: new interlock creation and old interlock

dissolution.

We first examine newly created audit committee interlocks. We identify all observations one year

before13

and one year after a new interlock is created. Results are reported in Table 5. The first two columns

are based on the continuous value of the |DACC| earnings quality variable. In the year before the audit

committee interlock is formed, is not significant, which is inconsistent with the firm-director matching

13 The observations one year before the interlock link established is not included in our original sample.

28

explanation. In contrast, in the year after the interlock, is significant. We find the similar results in the

third and fourth columns when using ELOADING earnings quality variable. The change in the relation

between the firms’ earnings qualities is consistent with the creation of the interlock facilitating information

transfers between the firms.

We next examine dissolved old audit committee interlocks. We identify all observations one year

before14

and one year after an interlock is dissolved. Results are reported in Table 6. In the first two columns,

we use the |DACC| earnings quality variable. When the interlock exists, is significant. In contrast, is

insignificant after the interlock is dissolved. We find similar results when we measure earnings quality as

ELOADING.

These results dovetail nicely with and substantially support the inferences from all of our analyses

above. Specifically, our evidence consistently supports the proposition that the similarity of interlocking

firms’ earnings qualities is due to information transfer and not due to their merely being similar firms. Also,

these sub-sample results reinforce the full-sample result that interlocks lead to information transfers by

demonstrating that firms’ accounting only becomes correlated in the presence of interlocks, and that these

effects come about quite rapidly, and dissipate just as quickly.

6.4 Is information transfer via interlocks symmetric?

We examine whether information transfer via audit committee interlocks is symmetric for good versus

bad accounting choices. In Table 7, we report the test results for Regression (3) and Regression (4). In the

left-hand side for information transfer of good earnings quality, none of the coefficients on GOODs (no

14 The observations one year before the interlock link established is not included in our original sample.

29

matter whether earnings qualities are measured by |DACC| or ELOADING), , is significant at 0.01 level,

indicating a lack of isomorphism for good earnings qualities at the interlocked firms. On the right-hand side,

in contrast, all the coefficients on BADs (no matter whether earnings qualities are measured by |DACC| or

ELOADING) are significant at 0.05 level or 0.01 level. This suggests that bad earnings quality is more

contagious than good earnings quality for interlocked firms, that is, “bad drives out good”.

6.5 Is information transfer via interlocks bidirectional?

Lastly, we examine how earnings quality changes in direction and magnitude via newly created

interlocks. In Panel A of Table 8, we report the change in earnings of qualities for information recipient firms.

In the first column, we examine how raw values of the change in |DACC|. The coefficient on Join Worse, β1,

is 0.016 while the coefficient on Join Better, β2, is -0.011, both significant at 0.001 level. This implies that for

the information recipient firm, |DACC| will increase by 1.6 percent (decrease by 1.1 percent) when it starts to

interlock with a worse (better) earnings quality firm via audit committee member. The results are similar

when we use decile ranking of |DACC| in the second column. The coefficient on Join Worse (β1) is 1.318

while the coefficient on Join Better (β2) is -0.532, both significant at 0.001 level, indicating that for the

information recipient firm, the decile ranking of |DACC| will increase by 1.3 ranks (decrease by 0.5 rank)

when it starts to interlock with a worse (better) earnings quality firm. For both cases, the F-tests for β1<-β2 are

significant at 0.10 and 0.01 level, indicating that the change in |DACC| is larger in magnitude when

interlocking with worse earnings quality firms than when interlocking with better earnings quality firms. In

the third and fourth column of Panel A, we show very similar results when we use ELOADING to measure

earnings qualities. In sum, we find for the information recipient firm, the contagion effect is larger when

30

interlocking with a worse earning quality firm than with a better earnings quality firm. Thus, these results are

generally similar to those reported Section 6.4, except that we do find significant information transfer from

better quality accounting firms improving their interlocked partner-firm’s accounting. However, the bad

effect is much more substantial, as one would conclude from the prior results.

In Panel B of Table 8 we report the results on whether the information sending firm’s earnings quality

also changes after new interlock formation. Based on the continuous value of |DACC| in the first column, the

coefficient on Join Worse, β1, is 0.009 while the coefficient on Join Better, β2, is -0.014, both significant at

0.001 level. However, the magnitude of β1 is less than that of β2, inconsistent with our findings that the bad

effect is larger than the good effect. In the second column, when we use the decile ranking of |DACC|, β1, is

0.919 and β2, is -0.640. The F-test for β1<-β2 is significant at 0.01 level, indicating that for the information

sending firm, as for the information recipient firms firm, interlocking with a worse firm has a larger

contagion effect than interlocking with a better firm. The third and the fourth columns show the results from

estimating our regression with the ELOADING earnings quality variable. As above, these results consistently

suggest that while both good and bad quality information affect the information sending firm. The F-test for

β1<-β2 for both the raw value and the decile ranking are significant at 0.01 level, indicating that interlocking

with a worse firm has a larger contagion effect than interlocking with a better firm. In sum, three cases out of

four from our tests indicate that for information sending firms interlocking with worse firms has stronger

effect than with better firm for initial firms.

6.6 Robustness: Eliminating restatement overlap

31

In order to make certain that our results are representative for various levels of earnings quality, rather

than being driven by only extreme case of accounting fraud, we exclude all restated firm-year observations

from our sample, and we continue to find similar results with this sub-sample. This result confirms that our

findings contribute to our understanding of the effects of social networks on firms’ accounting choices

beyond that shown in CTT (2010), and that they apply to the general population of firms.

6.7 Robustness: Controlling for interlock self-selection

As our sample excludes all S&P 1500 firm-year observations that lack interlocks, we may suffer

sample selection bias as board interlocks may be endogenously determined. In order to address this

selection-bias problem, we follow Li at al. (2007) and use a two-step Heckman selection model. In the first

step, we estimate the probability of a firm having an interlock, using all the S&P 1500 firm-year

observations in the sample period. Specifically, we use the following Probit model in the first step:

∑ (9.1)

where INTERLOCK is an indicator variable equal to one if a firm has one or more interlocks and zero

otherwise. Controls are the control variables in the Regression (1) excluding the total number of board

interlocks (#BOARD).

From the first step, we can estimate an Inverse Mills Ratio (

) to use in the second step. In the

second step, we estimate Regression (1) by adding the Inverse Mills Ratio derived from Regression (9.1).

[

]

∑ (9.2)

32

By introducing the two-step Heckman selection model, we account for the potential sample selection

bias problem. For the sake of parsimony, we do not provide the results using the Heckman selection model in

tabular form, but do find our results to remain the same when including the Inverse Mills Ratio in our

regressions. The coefficients of earnings qualities through the audit committee interlock are always positive

and significant, no matter whether we use |DACC| or ELOADING to measure earnings quality or whether we

use raw value or decile ranking in the tests. In addition, the coefficients for audit committee interlocks are

always more significant than the coefficients for board interlocks. In sum, we reach the same conclusion

after correcting for the self-selection bias.

7. Discussion and Conclusions

In this paper, we add to accounting research that focuses on the monitoring role of the board and the audit

committee by examining how the social network theory of information transfer between firms with

interlocked boards of directors applies to the diffusion of accounting choices. We find that interlocked firms’

accounting quality measures are significantly correlated, consistent with the notion that the quality of firms’

financial reporting is contagious. However, because this association could be due merely to the fact that

similar firms select similar directors, and not on account of information transfers causing them to be

associated, we also investigate how this association varies between times before interlocks are formed and

interlocks are dissolved, in comparison to, respectively, the year after an interlock is created and the year

before they are dissolved. We find in all cases, that firms do not experience significant associations between

their earnings quality measures when they are not interlocked, not before interlock creation nor after interlock

dissolution, but that they do experience a significant association in both the first year after the interlock is

33

formed and the last year before it is dissolved. These findings are strongly inconsistent with the idea that

similar firms merely select similar directors (including the same one) and strongly consistent with the social

network theory of information transfer.

By extending the models discussed above we also examine whether good earnings quality is as

contagious as bad. The old adage that “the bad drives out the good” and the apparent necessity of having to

enforce accounting rule applications suggests that there is legitimate concern on this subject. Unfortunately,

this adage was supported by our results. While we find some evidence consistent with good accounting

choices being transferred, thereby improving interlocked firm’s earnings quality, we find more substantial,

evidence that bad accounting, like disease, is much more contagious. In addition to being statistically

significant, our findings are economically meaningful. For example, the audit committee interlock

coefficients suggest increases of 3 percent and 11.3 percent for |DACC| and ELOADING respectively at the

information recipient firms (in Table 4). If firms are interlocked with multiple firms and worse accounting

choices are more likely to be transferred through the interlocks, then the overall influence of the social

context will be even greater in that the effects of worse practices may be amplified, while that of good

practices will be muted. Similarly, the economic significance in case of new interlock formation suggests that

significant information transfer occurs; the audit committee interlock coefficients suggest increases of 7.4

percent and 8.3 percent for |DACC| and ELOADING respectively at the information recipient firms after a

new interlock has been formed (in Table 4). Overall, we provide preliminary evidence about the importance

of the social context for accounting choices and recommend that future researchers consider both monitoring

and social context factors simultaneously in understanding firms’ accounting choices.

34

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Table 1: Sample formation, 1999-2006

# of firm-year obs. # of

firm-year-director

obs.

All S&P1500 firms from Risk Metrics 12,611 118, 753

Firms with information in COMPUSTAT 11,903 111, 895

# of firm-year obs. # of firm-firm-year

interlock obs.

Firms with board interlock, audit committee interlock or both 8,212 39,807 a

Firms with audit committee interlock 16,861 b

Firms with board interlock 22,946

Audit committee interlock is a dummy variable equal to one when an interlock is through an audit committee

member, and zero otherwise. Board interlock is a dummy variable equal to one if an interlock is through a

director not serving on audit committee, and zero otherwise.

a: When the same firm-firm interlock link exists through different directors, we count it as one interlock

rather than several interlocks.

b: If an interlock link is through both audit committee member(s) and other director(s), we count it as one

audit committee interlock.

38

Table 2: Descriptive statistics

Board interlock, audit committee interlock, and auditor link

Variable N Percentage

Board interlock 22,946 57.64%.

Audit committee interlock 16,861 42.36%

Auditor link 7,829 19.67%

The information sending firm (s)

Variable Mean Std Dev Q1 Median Q3

|DACCs| 0.04 0.05 0.01 0.02 0.05

ELOADINGs -0.09 0.39 -0.36 -0.13 0.07

The information recipient firm (r)

Variable Mean Std Dev Q1 Median Q3

|DACCr| 0.04 0.06 0.01 0.02 0.05

ELOADINGr -0.08 0.41 -0.38 -0.12 0.09

SIZE 8.36 1.53 7.27 8.24 9.36

LEVERAGE 0.24 0.19 0.08 0.22 0.35

M/B 2.99 3.34 1.51 2.25 3.58

SALE_VOL 0.44 0.33 0.22 0.37 0.56

LOSS 0.18 0.38 0.00 0.00 0.00

ABEMPLOYEE -0.10 0.48 -0.13 -0.05 0.03

LEASE 0.86 0.35 1.00 1.00 1.00

#BOARD 6.40 5.54 2.00 5.00 9.00

G-INDEX 9.45 2.59 8.00 9.00 11.00

DUALITY 0.81 0.39 1.00 1.00 1.00

INDEPENDENCE 0.69 0.16 0.57 0.71 0.82

INST SHARE 0.72 0.23 0.59 0.75 0.86

s denotes the information sending firm and r denotes the information recipient firm in an interlock link.

Audit committee interlock is a dummy variable equal to one when an interlock is through an audit committee

member, and zero otherwise.

Board interlock is a dummy variable equal to one if an interlock is through a director not serving on audit

committee, and zero otherwise.

Auditor link is a dummy variable equal to 1 if the link if the initial firm and the later firm share the same

auditor and equal to 0 otherwise.

|DACC| is the absolute value of discretionary accruals, estimated using the cross-sectional modified Jones

(1991) model. Refer to section 5.2 for more details.

ELOADING is the coefficient on AQfactor estimated from the regression: (

) , using a 1-year window. Refer to section 5.2 for more

details.

SIZE is the log of market value of equity (MV), calculated as the multiple of market price (PRCC) * share

outstanding (CSHO).

LEVERAGE is calculated as long-term debt (DLTT) plus debt in current liabilities (DLC) over average total

assets (AT).

M/B is the market-to-book ratio, calculated as the market value of equity (MV) divided by the book value of

equity (CEQ).

SALE_VOL is sales volatility, calculated as the standard deviation of sales (SALE) over year t-4 to year t.

LOSS is an indicator variable, equal to one when earnings before extraordinary items (IB) are negative, and

zero otherwise.

39

ABEMPLOYEE is the abnormal change of employees, calculated as the number of employees (EMP) for year

t minus the number in year t-1, scaled by the number in year t-1, less total assets (AT) at year t minus that of

year t-1, scaled by assets at year t-1.

LEASE is an indicator variable equal to one if a firm’s future operating lease obligations (MRC1, MRC2,

MRC3, MRC4, or MRC5) are greater than zero, and zero otherwise.

# BOARD is the number of interlocks through directors.

G-INDEX is the Governance Index as in Gompers, Ishii, Metrick (2003). DUALIDITY is a dummy variable equal to one if a firm’s CEO is also the chairman of board, and zero

otherwise.

INDEPENDENCE is the percentage of independent board members on board.

INST SHARE is the percentage of institutional share holdings.

40

Table 3: Pearson and Spearman correlations

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) (15) (16)

(1) |DACCs| 0.30 0.08 0.08 -0.15 -0.06 -0.02 0.04 0.36 -0.04 0.07 -0.08 -0.08 -0.05 -0.02 -0.08

(2) ELOADINGs 0.15 0.12 0.13 0.00 -0.06 0.00 -0.06 0.28 -0.02 0.09 -0.03 -0.08 -0.03 -0.04 -0.09

(3) |DACCr| 0.06 0.07 0.25 -0.05 -0.03 -0.01 -0.03 0.08 0.01 0.00 -0.05 -0.05 -0.02 -0.03 -0.03

(4) ELOADINGr 0.04 0.05 0.12 0.00 -0.05 0.01 -0.04 0.09 0.01 0.02 -0.03 -0.06 -0.01 -0.04 -0.04

(5) SIZE -0.15 0.04 -0.07 0.01 -0.02 0.32 -0.23 -0.25 -0.02 -0.03 0.52 -0.04 0.12 -0.11 0.10

(6) LEVERAGE -0.12 -0.08 -0.03 -0.04 -0.01 -0.08 -0.19 0.12 -0.07 -0.14 0.12 0.04 0.09 0.01 -0.01

(7) M/B 0.02 -0.01 -0.02 0.02 0.45 -0.14 0.03 -0.16 0.00 0.06 0.15 -0.06 -0.01 -0.02 -0.01

(8) SALE_VOL 0.11 -0.06 -0.01 -0.04 -0.24 -0.19 0.05 -0.02 0.05 0.18 -0.04 0.05 -0.02 0.09 0.01

(9) LOSS 0.24 0.18 0.07 0.07 -0.24 0.09 -0.27 -0.03 0.01 0.05 -0.08 -0.07 -0.03 -0.02 -0.07

(10) ABEMPLOYEE 0.03 -0.03 0.01 0.00 -0.10 -0.02 -0.05 0.07 0.07 0.05 -0.08 0.02 -0.03 -0.01 0.04

(11) LEASE 0.07 0.10 0.00 0.02 -0.03 -0.14 0.09 0.21 0.05 0.03 0.03 -0.01 -0.02 -0.01 -0.06

(12) #BOARD -0.07 0.00 -0.06 -0.01 0.53 0.14 0.16 0.01 -0.08 -0.08 0.02 0.11 0.22 -0.02 0.18

(13) G-INDEX -0.07 -0.03 -0.03 -0.05 -0.02 0.09 -0.08 0.06 -0.07 -0.03 -0.01 0.14 0.12 0.52 0.24

(14) DUALITY -0.07 -0.01 -0.01 0.01 0.13 0.11 -0.03 -0.01 -0.03 -0.03 -0.02 0.23 0.12 0.02 0.13

(15) INDEPENDENCE -0.05 -0.06 -0.03 -0.05 0.09 0.05 -0.01 0.03 -0.06 -0.02 -0.06 0.21 0.21 0.13 0.08

(16) INST SHARE -0.04 -0.06 -0.02 -0.04 -0.05 -0.11 0.03 0.03 -0.10 -0.02 0.16 -0.15 0.05 -0.07 0.03 0.16

Pearson (Spearman) correlations are above (below) the diagonal in Panel B. Bold numbers in Panel B indicate significant <0.01 level.

Please refer to Table 2 for detailed definition of the all the variables.

41

Table 4: The contagion effect of board and audit committee interlocks

∑

EQ measured by |DACC| EQ measured by ELOADING

Raw value Decile Ranking Raw value Decile Ranking

EQs,t * Board interlock (β1) -0.003 -0.005 0.067 0.030

[0.808] [0.614] [0.000] [0.001]

EQs,t * Audit committee interlock (β2) 0.047 0.033 0.136 0.101

[0.000] [0.001] [0.000] [0.000]

EQs,t *Auditor link 0.003 -0.007 0.036 0.021

[0.834] [0.511] [0.044] [0.035]

SIZE -0.003 -0.160 0.205 1.120

[0.000] [0.000] [0.000] [0.000]

LEVERAGE -0.009 -0.078 0.008 0.073

[0.001] [0.000] [0.002] [0.000]

M/B 0.000 0.080 -0.099 -0.424

[0.746] [0.000] [0.000] [0.008]

SALE_VOL 0.004 0.015 -0.004 -0.032

[0.063] [0.208] [0.000] [0.000]

LOSS 0.031 1.240 -0.045 -0.306

[0.000] [0.000] [0.002] [0.005]

ABEMPLOYEE -0.012 -0.028 -0.013 -0.037

[0.000] [0.001] [0.128] [0.554]

LEASE 0.001 0.290 0.010 -0.008

[0.446] [0.001] [0.409] [0.931]

#BOARD 0.000 0.024 -0.001 0.002

[0.322] [0.070] [0.302] [0.692]

G-INDEX -0.001 -0.054 -0.011 -0.069

[0.000] [0.000] [0.000] [0.000]

DUALITY 0.003 0.158 0.033 0.225

[0.006] [0.015] [0.000] [0.001]

INDEPENDENCE 0.011 0.033 -0.037 0.143

[0.000] [0.000] [0.106] [0.403]

INST SHARE -0.013 -0.021 0.051 0.238

[0.000] [0.031] [0.008] [0.099]

INTERCEPT 0.073 4.780 -0.033 3.710

[0.000] [0.000] [0.321] [0.000]

Test:β1=β2

F-value 14.47 17.47 12.74 13.45

p-value [0.000] [0.000] [0.000] [0.000]

Year and Industry Fixed Effects Yes Yes Yes Yes

Industry Fixed Effects Yes Yes Yes Yes

Observations 10,288 10,288 8,979 8,979

Adjusted RSQ 0.2260 0.3100 0.3420 0.2020

p-value is reported in [ ].

Please refer to Table 2 for detailed definition of the all the variables.

42

Table 5: The contagion effect of audit committee interlocks: New interlock creation

∑

EQ measured by |DACC| EQ measured by ELOADING

1 year before 1 year after 1 year before 1 year after

EQs,t 0.019 0.074 0.022 0.083

[0.518] [0.033] [0.652] [0.011]

SIZE 0.001 -0.005 -0.019 0.048

[0.405] [0.001] [0.107] [0.000]

LEVERAGE -0.034 0.038 -0.034 -0.151

[0.003] [0.000] [0.685] [0.045]

M/B 0.000 -0.001 -0.002 0.004

[0.604] [0.192] [0.650] [0.258]

SALE_VOL 0.009 -0.011 -0.133 -0.020

[0.299] [0.129] [0.034] [0.716]

LOSS 0.040 0.011 0.057 0.250

[0.000] [0.006] [0.143] [0.000]

ABEMPLOYEE 0.022 -0.010 0.095 0.163

[0.004] [0.087] [0.097] [0.000]

LEASE 0.013 0.007 0.026 0.169

[0.060] [0.300] [0.625] [0.000]

#BOARD -0.001 -0.001 0.001 -0.014

[0.029] [0.012] [0.732] [0.000]

G-INDEX -0.001 -0.001 -0.002 0.003

[0.072] [0.284] [0.677] [0.571]

DUALITY 0.005 -0.003 -0.128 0.056

[0.349] [0.466] [0.001] [0.107]

INDEPENDENCE 0.006 -0.006 0.005 0.114

[0.619] [0.603] [0.958] [0.151]

INST SHARE -0.014 -0.019 -0.107 -0.022

[0.169] [0.002] [0.158] [0.596]

INTERCEPT 0.046 0.115 0.250 -0.484

[0.012] [0.000] [0.070] [0.000]

Year and Industry Fixed Effects Yes Yes Yes Yes

Industry Fixed Effects Yes Yes Yes Yes

Observations 1,006 1,152 797 930

Adjusted RSQ 0.1800 0.2030 0.1210 0.3580

p-value is reported in [ ].

Please refer to Table 2 for detailed definition of the all the variables

43

Table 6: The contagion effect of audit committee interlocks: Old interlock dissolution

∑

EQ measured by |DACC| EQ measured by ELOADING

1 year before 1 year after 1 year before 1 year after

EQs,t 0.080 -0.006 0.130 0.037

[0.017] [0.832] [0.000] [0.308]

SIZE -0.004 -0.002 0.023 0.053

[0.002] [0.132] [0.012] [0.000]

LEVERAGE 0.007 0.030 -0.201 -0.047

[0.476] [0.001] [0.001] [0.531]

M/B -0.001 0.000 0.009 0.004

[0.009] [0.755] [0.006] [0.341]

SALE_VOL -0.001 0.005 0.124 0.190

[0.842] [0.456] [0.008] [0.001]

LOSS 0.034 0.035 0.277 0.149

[0.000] [0.000] [0.000] [0.000]

ABEMPLOYEE -0.010 -0.001 -0.024 0.016

[0.002] [0.827] [0.227] [0.462]

LEASE 0.012 -0.004 0.142 0.008

[0.035] [0.390] [0.000] [0.851]

#BOARD -0.001 [0.000] -0.004 -0.006

[0.042] [0.248] [0.034] [0.030]

G-INDEX -0.001 -0.001 -0.006 0.004

[0.022] [0.138] [0.162] [0.415]

DUALITY 0.004 0.002 0.044 0.117

[0.414] [0.642] [0.171] [0.009]

INDEPENDENCE -0.007 0.018 -0.038 -0.170

[0.535] [0.087] [0.604] [0.056]

INST SHARE -0.053 -0.001 -0.102 -0.095

[0.000] [0.877] [0.071] [0.189]

INTERCEPT 0.103 0.027 -0.364 -0.617

[0.000] [0.086] [0.001] [0.000]

Year and Industry Fixed Effects Yes Yes Yes Yes

Industry Fixed Effects Yes Yes Yes Yes

Observations 1,370 1,021 847 689

Adjusted RSQ 0.3000 0.1990 0.3290 0.3130

p-value is reported in [ ].

Please refer to Table 2 for detailed definition of the all the variables

44

Table 7: The contagion effect of audit committee interlocks: Extremely good and bad earnings quality

∑

∑

EQ measured by EQ measured by

|DACC| ELOADING |DACC| ELOADING

GOODs,t ( ) -0.029 0.000 BADs,t ( ) 0.207 0.375

[0.677] [0.996] [0.011] [0.000]

GOODs,t *Auditor Link -0.090 0.051 BADs,t *Auditor Link 0.063 0.226

[0.503] [0.746] [0.669] [0.136]

SIZE 0.077 -0.120 SIZE -0.094 -0.061

[0.001] [0.000] [0.000] [0.021]

LEVERAGE 0.396 0.043 LEVERAGE -0.500 -1.250

[0.035] [0.835] [0.004] [0.000]

M/B 0.026 0.010 M/B -0.010 -0.067

[0.002] [0.292] [0.270] [0.000]

SALE_VOL -0.231 0.403 SALE_VOL -0.130 -0.468

[0.079] [0.002] [0.291] [0.001]

LOSS -0.325 -0.193 LOSS 0.786 0.633

[0.000] [0.027] [0.000] [0.000]

ABEMPLOYEE 0.044 -0.157 ABEMPLOYEE -0.280 0.020

[0.583] [0.017] [0.000] [0.823]

LEASE -0.091 -0.018 LEASE -0.039 -0.021

[0.336] [0.861] [0.701] [0.876]

#BOARD -0.017 -0.004 #BOARD -0.009 -0.019

[0.001] [0.516] [0.107] [0.009]

G-INDEX 0.058 -0.037 G-INDEX -0.029 -0.109

[0.000] [0.007] [0.016] [0.000]

DUALITY 0.134 -0.132 DUALITY 0.145 0.380

[0.078] [0.125] [0.056] [0.000]

INDEPENDENCE -0.058 0.311 INDEPENDENCE 0.590 -0.331

[0.765] [0.160] [0.004] [0.170]

INST SHARE 0.322 -0.666 INST SHARE -0.395 -0.119

[0.055] [0.000] [0.014] [0.527]

INTERCEPT -2.240 -5.820 INTERCEPT 0.079 -2.700

[0.000] [0.994] [0.820] [0.983]

45

Year and Industry

Fixed Effects Yes Yes

Year and Industry

Fixed Effects Yes Yes

Industry Fixed

Effects Yes Yes

Industry Fixed

Effects Yes Yes

Observations 4,428 3,415 Observations 4,047 3,526

Adjusted RSQ 0.1030 0.1480 Adjusted RSQ 0.1380 0.2860

p-value is reported in [ ].

GOOD (BAD) is an indicator variable equals to one if the earnings quality is in the lowest (highest) quintile

and zero otherwise.

Please refer to Table 2 for detailed definition of all the other variables

46

Table 8: The bidirectional changes in earnings quality on creation of audit committee interlocks

Panel A: The information recipient firm

EQ measured by |DACC| EQ measured by ELOADING

Raw value Decile Ranking Raw value Decile Ranking

Join worse (β1) 0.016 1.318 0.208 1.74

[0.000] [0.000] [0.000] [0.000]

Join better(β2) -0.011 -0.532 -0.087 -0.641

[0.000] [0.000] [0.000] [0.000]

Test: β1< -β2

F-Statistics 2.03 21.19 15.15 30.47

p-value [0.077] [0.000] [0.000] [0.000]

Panel B: The information sending firm

EQ measured by |DACC| EQ measured by ELOADING

Raw value Decile Ranking Raw value Decile Ranking

Join worse (β1) 0.009 0.919 0.116 1.138

[0.001] [0.000] [0.000] [0.000]

Join better(β2) -0.014 -0.640 -0.051 -0.666

[0.000] [0.000] [0.000] [0.000]

Test: β1< -β2

F-Statistics 2.26 2.61 7.13 6.93

p-value [0.066] [0.053] [0.004] [0.004]

The above regression is without intercept.

p-value is reported in [ ].

is the change in earnings quality one year after minus one year before the formation of a new audit

committee interlock; is an indicator variable equal to one with worse earnings quality firm and

equal to zero otherwise; is an indicator variable equal to is an indicator variable equal to one

with better earnings quality firm and equal to zero otherwise.

Please refer to Table 2 for detailed definition of other variables.