Ideology and political awareness: Under what conditions ideology affects voting behavior in Mexico?

The 2012 presidential election in Mexico

Rodrigo Castro Cornejo

rcastroc@nd.edu

Department of Political Science University of Notre Dame 217 O'Shaughnessy Hall Notre Dame, IN 46556

Abstract: In this paper using data from the 2012 CIDE-Comparative Study of Electoral Systems (CSES) I found that the effect of ideology on vote choice is contingent upon specific conditions. Specifically, I find that voters’ ideological orientations on vote choice are stronger when voters are aware of the ideological differences between parties. And the effect is stronger when the perceived ideological difference is larger. This finding is relevant because it confirms that in an increasingly institutionalized party system, voters become aware of what major parties represent ideologically and this information is relevant when choosing among political alternatives at election time.

Draft: Sept 2013

Please do not quote without the author’s permission Paper prepared for presentation at the 7º Congreso Latinoamericano de Ciencia Política, Bogotá,

Colombia, Sept , 2013.

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The goal of my paper is to explain how ideology (IV) affects voting behavior (DV) in

Mexico. While some authors argue that there is a strong relationship between individual

ideological orientations and voter’s choices (Moreno 2006), others scholars have shown that the

impact of the left-right ideological continuum is contingent upon the polarized character of the

campaign (Beltrán, 2009). In this paper I argue that ideology matters, but the effects are

contingent under specific conditions. In particular, the effect of voters’ ideological orientations

on vote choice will be stronger when voters are aware of the ideological differences between

parties. To test this hypothesis I will use the dataset of the 2012 CIDE-Comparative Study of

Electoral Systems (CSES) post-electoral study which is a collaborative program of research

among election study teams from around the world that include a common module of survey

questions in their post-election studies.

This paper is structured in the following way. In the first section I will refer to the

literature that posits that voters’ ideological preferences have a direct impact on their electoral

decisions. Second, I will present the testable hypothesis of this paper, and explain the

methodology to test them. In the third section, I will present my models and results for the 2012

presidential election in Mexico, where I find that voters’ ideological preferences had a significant

impact on their vote choice, especially among voters that are aware of ideological differences

among political parties. This finding is relevant because it confirms that in an increasingly

institutionalized party system, voters are aware of what major parties represent programmatically

and ideologically (Mainwaring and Scully, 1995), and this information is relevant when taking

electoral decisions.

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1. Ideology and vote choice A basic assumption in the literature about voting behavior is that voters tend to minimize

the cost of acquiring information (Downs 1957). In this regard, voters will use informational

cues or heuristics, which are simplifications about complex aspects of political competition, in

order to make electoral decisions (Erikson, Macuen and Stimson, 2002; Lupia y McCubbins,

1998; Page and Shapiro, 1992; Popkin, 1994; Sniderman, Brody and Tetlock, 1991). Party

identification and ideology are the most common cues used by voters to choose among

alternatives and evaluate parties, candidates, and their policies.

In this respect, ideology is a tightly constrained belief system that provides a relatively

stable perspective from which an individual can think about major questions in public policy

(Converse 1964). A common assumption in the literature is that ideology is an attitude structure.

The literature defines attitude structure as a “common element” that “underlies the ways that an

individual reacts to different political issues” (203). The central psychological function of this

structure is to link specific opinions and general value orientations. Lewis-Beck et al (2008)

argue that we should think of attitude structures as hierarchically organized mental constructs.

In this sense, ideology is a set of beliefs and evaluations that are crystallized, interlocked,

and broad in scope. Furthermore, an ideological attitude structure is grounded in broad

assumptions about the nature of society and appropriate social objectives; namely, an ideology

summarizes a person’s overall stance toward the political world (Lewis-Beck et al 2008, 207).

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1.1. When should we expect that ideology will affect vote choice? The literature on mass opinion constraint identifies sources of constraint that may tie

mass political orientations together horizontally (typing various types of issue attitudes together

into something approaching a single ideological dimension) or vertically (truing the core values

to particular policy attitudes and then to political behavior) (Campbell et al, The American Voter,

Zaller 1972) and affect political behavior.

Converse (1964) identifies three key sources of constraint: logical, psychological and

social. Carmines and Stimson (1989) add a fourth source of constraint that is political: an

electoral constraint. The logical constraint can be a potent source of opinion constraint when

there is an inherent rationale for the relationship between political objects, so that simply

“thinking” about a set of idea-elements may held them together. But Converse argues that it is

rarely a source of constraint in the mass public, because most citizens think little about politics

and have limited knowledge of most political objects. Additionally, such logic is less likely to be

clearly perceived under some conditions. For example, it may be “logical” that the PAN --that is

usually portrayed as the most “conservative” party-- should have conservative ideological

positions. Nonetheless, although the PAN usually support traditional moral policies, it is less

clear that the PAN follows a clear neoliberal agenda, especially among the most “Christian

Democrat” members of the party. And this pattern repeats between the other two major parties in

Mexico.

Psychological and social factors do not depend on high levels of political information or

knowledge, but on personal experiences. Psychological constraints tie attitudes together when

life experiences package attitudes with group identifications. Nonetheless, group identifications

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linked to political parties are less clear in Mexico than in American politics in which unions, or

religious communities and traditions have strong connections with political parties.

According to Carmines and Stimson (1989), when parties and candidates emphasize and

take clearly distinct stands on particular policy issues, the horizontal and vertical connection

between attitudes towards the issues, related socio-demographic orientations and political

behavior tend to increase. At the individual level, citizens who care about policy issues and

recognize party and candidate differences on them display greater constraint with regard to those

issues than do other citizens. This is where this papers stands. I expect that the influence of

ideology on vote choice should be stronger among voters that are aware of the ideological

differences between political parties in Mexico.

1.2. Ideology in Mexico Ideological orientations seem to play a key role in explaining the process through which

citizens evaluate and made their political decisions. In other words, the left-right continuum

serves as a simple and efficient mechanism of political space through which citizens and political

parties communicate (Knight 1985; Fuchs and Klingemann 1990; Hinich and Munger 1994).

Nonetheless, countries that have recently experienced transition to democracy and, therefore,

with a shorter period of democratic experience have had less exposure to ideological information

structured by "left/right" concepts. Is in this context where a case like Mexico is particularly

interesting.

Mexico’s transition to democracy came to a critical point in 2000, when the presidential

election brought political alternation after 71 years of a hegemonic party system led by the

Institutional Revolutionary Party (PRI) who was defeated by Vicente Fox, the National Action

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Party (PAN) candidate. In this sense, as argued by Moreno (1999), the democratic-authoritarian

dimension of political competition was only temporary; its centrality to party competition was

bounded by the permanence of the ruling party in power. All that had changed by 2006, when the

PAN was the incumbent party and the PRI suffered a dramatic drop in electoral support, and

ranked a distant third in the national vote share. The PAN won the presidency and the leftist

Party of the Democratic Revolution (PRD) reached the second place, with only 0.56% of

difference of the national vote share. The 2006 presidential election was the first time in post

hegemonic-party era that the left-right dimension became relevant in the political debate.

In fact, Moreno finds a remarkable redistribution of the left-right self-placement scale:

“there is a changing underlying meaning of left and right, from a regime cleavage that dominated

the early stages of party competition in the 1990`s, to a left-right divide that increasingly relies

on economic issues” (Moreno 2006). Which confirms a similar pattern in new democracies in

Latin America and in post-soviet Eastern Europe in which the left-right labels are increasingly

relevant as a tool or political heuristic of political parties and candidates to communicate.

Nonetheless, as argued by Zechmeister and Corral (2013), although ideological labels are

theoretically useful tools with which individuals engage in politics, their actual significance

varies. Specifically, they find that, although education, political interest, and political

sophistication help citizens place themselves on the ideological continuum, context also matters

such that polarization (positively), fragmentation (negatively), and volatility (negatively) affect

left–right response. In this way, we can conceive that ideological labels in Latin America hold

important potential for orienting citizens within the political arena, but their utility is constrained

in important ways at both the individual and contextual levels.

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This echoes a similar finding by Beltran (2009) regarding the 2006 Mexican presidential

election and how context has strong influence on the utility of ideological orientations among

voters. Beltrán suggests that ideological views had some impact on the electoral choice,

particularly through the influence of the polarized character of the campaign. The empirical

evidence shows that the correct location of the candidates had different effects on the

contenders. Locating López Obrador as a left-wing candidate resulted in a lower probability

of voting for him, whereas the correct location of the incumbent Felipe Calderón increased the

probability of casting a vote favorable to him.

1.3. Ideology and vote choice (1997-2012) In the following graphs I show how ideological orientations have shaped vote choice

across time since 19971. Interestingly, ideology is not statistically significant in 1997, but other

factors tend to explain vote choice. In 2000, 2003 and 2006 elections, and following the

expectations of an increasingly institutionalized party system, ideology became statistically

significant but only when assessing the vote for the PRD (center-left party) relative to the PAN

(center-right party). In the case of the 2012, the same pattern continues, ideology is substantively

and statistically significant relative to the PRD. In other words, there are no clear ideological

differences between panistas and priístas.

In the case of the PAN there is an interesting pattern (see graph). In the following graph,

the predicted probabilities for 1997, 2000 and 2003 show that the PAN received votes from

leftist, centrist and rightists voters, there is no slope or variation across ideology. It is until 2006,

                                                                                                               1 1997, 2003, and 2009 were legislative elections. Meanwhile, 2000, 2006, and 2012 were presidential elections. The models that I ran to produce these graphs are located in the Appendix: Table A1, A2 and A3.

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2009, and 2012 (although weaker) when the PAN began receiving more votes from the rightist

voters.

Quite the opposite in the case of the PRI, meanwhile in the elections before 2006 this

party tended to receive more votes from rightists voters, in 2006 and 2009 the slope is almost

marginal, there is no variation across ideology when voting for the PRI. But interestingly, in the

2012 presidential election, when the PRI returned to power, the PRI received votes from the

most rightist voters. In other words, it seem that the PRI gain that part of the electorate that in the

last two elections (2006 and 2009) were supporting the PAN.

0.2

.4.6

.81

PAN

0 2 4 6 8 10

1997

0.2

.4.6

.81

PAN

0 2 4 6 8 10

2000

0.2

.4.6

.81

PAN

0 2 4 6 8 10

2003

0.2

.4.6

.81

PAN

0 2 4 6 8 10

2006

0.2

.4.6

.81

PAN

0 2 4 6 8 10

2009

0.2

.4.6

.81

PAN

0 2 4 6 8 10

2012

Ideology - 0: left, 10:right

Predicted probabilitiesPAN: Ideology and Vote Choice (1997-2012)

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And finally, in the case of the PRD, this party has always received more voters from the

left. With these results we confirm that ideology is becoming more relevant among the electorate

after the collapse of the hegemonic-party system led by the PRI, turning the left-right dimension

a relevant variable. But the 2012 change slightly the scenario. The PAN is still gaining more

votes from the right, but less than in the ideological and polarized 2006 presidential election and

the 2009 legislative election. The PRI is returning to a pre-2000 scenario (before they lost the

presidential power), winning voters votes especially from the most rightist voters. And the PRD

continues to win votes from the leftists voters, and this relationship is stronger in 2012.

0.2

.4.6

.81

PRI

0 2 4 6 8 10

1997

0.2

.4.6

.81

PRI

0 2 4 6 8 10

2000

0.2

.4.6

.81

PRI

0 2 4 6 8 10

2003

0.2

.4.6

.81

PRI

0 2 4 6 8 10

2006

0.2

.4.6

.81

PRI

0 2 4 6 8 10

2009

0.2

.4.6

.81

PRI

0 2 4 6 8 10

2012

Ideology - 0: left, 10:right

Predicted probabilitiesPRI: Ideology and Vote Choice (1997-2012)

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2. Hypothesis and empirical strategy In this paper I argue that the impact of ideology on vote choice will be stronger among

those voters that are aware of the ideological differences between major political parties.

According to the 2012 CIDE-Comparative Study of Electoral Systems (CSES) post-electoral

study, voters do perceive ideological differences between them. In the next graph I report the

ideological position of political parties. The PRD is the most leftist party perceived among the

electorate; it is located on the 3.4 of the 0-10 ideological scale. Interestingly, the PAN is located

on the right of the scale (6.5), but slightly at the left of the PRI (7.1). This location is interesting

because since 2000, when the PRI lost the presidential power, the PAN was viewed as the most

rightist political party in Mexico (see graph). In other words, the PRI ideological location is

returning to a pre-2000 scenario, before they lost the presidential power.

0.2

.4.6

.81

PRD

0 2 4 6 8 10

1997

0.2

.4.6

.81

PRD

0 2 4 6 8 10

2000

0.2

.4.6

.81

PRD

0 2 4 6 8 10

2003

0.2

.4.6

.81

PRD

0 2 4 6 8 10

2006

0.2

.4.6

.81

PRD

0 2 4 6 8 10

2009

0.2

.4.6

.81

PRD

0 2 4 6 8 10

2012

Ideology - 0: left, 10:right

Predicted probabilitiesPRD: Ideology and Vote Choice (1997-2012)

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In this context, the main hypothesis of this paper is the following: Hypothesis: The effect of ideology on vote choice will be stronger among those voters that are aware of the ideological differences between major political parties The dependent variable of this paper is vote choice. In Mexico there are three relevant

political parties: PAN, PRI and PRD2. Because of that I will run multinomial logistic regression.

                                                                                                               2 The DV also includes a fourth category “other political parties” that only represents a marginal percent of the sample. I have excluded those cases in my analysis..

PRD PRIPAN

0 1 2 3 4 5 6 7 8 9 10

Ideological scale 0: left; 10: right

2012 Presidential Election

Ideological position of political parties

PAN PRI PRD

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Multinomial logistic regression is used when the dependent variable is nominal, in other words,

there is a set of categories that cannot be ordered in any meaningful way and consists of more

than two categories3. One of the categories of the dependent variable is designated as the

reference category. In my models, vote for the PRI is the reference category. From a theoretical

and also empirical reason, no categories were necessary to be combined. In fact, I computed LR

tests of whether two outcomes can be combined and rejected the null hypothesis that all

coefficients except intercepts associated with a given pair of alternatives are 0.

IDEOLOGY will be operationalized with the following question of the Comparative

Study of Electoral Systems (CSES) survey: “In politics people sometimes talk of left and right.

Where would you place yourself on a scale from 0 to 10 where 0 means the left and 10 means the

right”. The next graph shows the distribution of the Mexican electorate in the 2012 presidential

election. The mean is 6.6 (std dev = 2.7) which clearly illustrates that voters were closer to the

right.

                                                                                                               3 For a DV with M categories, this requires the calculation of M-1 equations, one for each category relative to the reference category, to describe the relationship between the DV and the IVs.

010

2030

40

0 1 2 3 4 5 6 7 8 9 10Ideology (Left-Right)

2012: Ideological self-placement (%)

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To evaluate if the electorate is aware of the ideological distance of the major political

parties, I used the following question: “In politics people sometimes talk of left and right. Using

the scale the following scale where 0 means left and 10 means right. Where would you place

the…?”. It is important to mention that I have tested two alternative ways to operationalize

awareness. In the first case, I calculate the absolute difference between the ideological position

(IDEOLOGICAL DIFFERENCE) of Mexican parties:

IDEOLOGICAL DIFFERENCE: | Ideological position PAN – Ideological position PRD |

IDEOLOGICAL DIFFERENCE: | Ideological position PRI – Ideological position PRD |

With this operationalization I will be able to evaluate if IDEOLOGY has a stronger impact on

vote choice among voters that perceive differences between parties. Since it is the absolute

difference, I do not assume if this is the correct ideological difference between the major political

parties, I only evaluate the impact of perceiving an ideological distance between them.

The second operationalization is slightly different. I assume that, in fact, the PRD is the

leftist political party in Mexico and the PRI and the PAN are located at the right of the

ideological scale relatively to the PRD. Then I calculate the difference between each pair. For

example, between the PAN (right) and the PRD (left); positive values imply a correct ideological

difference perceived by the respondent, negative values imply an incorrect ideological

difference. With this operationalization, I will not only be able to test if, in fact, IDEOLOGY has

a stronger impact on vote choice among voters that perceive differences between parties, but

also, I will verify if a correct perceived ideological difference encourages a stronger effect of

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IDEOLOGY on vote choice. I call this difference the SUBSTANTIVE IDEOLOGICAL

DIFFERENCE4:

SUBSTANTIVE IDEOLOGICAL DIFF.: Ideological position PAN – Ideological position PRD

SUBSTANTIVE IDEOLOGICAL DIFF.: Ideological position PRI – Ideological position PRD

My models will also include PARTY ID since it is considered as one of the most stable

characteristics of the Mexican electorate and a good predictor of voting behavior (Domínguez y

McCann 1995, Poiré 1999, Moreno 2003, Estrada 2005, Moreno and Méndez 2007, Moreno

2007, Guardado 2009). I include in my models j-1 dummy variables of party identification: PAN,

PRD, and INDEPENDENTS (PRI is the base category). Additionally, I will include control

variables such as GENDER, AGE and EDUCATION.

2012 presidential election – Descriptive statistics

Variable Obs Mean Std. Dev. Min Max Ideology 1812 6.6 2.7 0 10

Party ID: PAN 2312 0.1 0.3 0 1 Party ID: PRI 2312 0.2 0.4 0 1 Party ID: PRD 2312 0.1 0.3 0 1

Party ID: Independent 2312 0.6 0.5 0 1 Ideological Difference |PRI-PRD| 1769 4.9 3.3 0 10

Substantive Ideological Diff. PRI-PRD 1769 3.7 4.6 -10 10 Ideological Difference |PAN-PRD| 1750 4.5 3.3 0 10

Substantive Ideological Diff. PAN-PRD 1750 3.2 4.6 -10 10 Age 2400 0.6 0.5 0 1

Education 2400 42.7 16.8 18 98 Female 2387 3.9 2.1 0 9

                                                                                                               4 In the Appendix, I report the distribution of both variables: IDEOLOGICAL DIFFERENCE and SUBSTATANTIVE IDEOLOGICAL DIFFERENCE.

  15

3. Results

In this first section I will present the results of the multinomial logistic regressions

models; the parameter estimates are relative to the referent group (PRI). In the 2012 presidential

election, the left-right dimension was empirically and substantively relevant among the

electorate. Ideology is statistically significant to the 0.1% level (model 1), for the vote for the

PRI relative to PRD. This remains statistically significant even when controlling for additional

variables such as party identification, age, education and gender (model 2 and 3). Between the

PRI and the PAN, ideology is not statistically significant.

Multinomial Logistic regression Dependent Variable: VOTE CHOICE (PRI base category)

(1) (2) (3)

PAN PRD PAN PRD PAN PRD

Ideology 0.02 -0.39*** 0.01 -0.33*** 0.01 -0.33***

(0.03) (0.03) (0.03) (0.03) (0.04) (0.03) Party ID: PAN 5.56*** 2.31*** 5.58*** 2.33***

(0.48) (0.47) (0.48) (0.47) Party ID: PRD 2.96*** 5.81*** 3.12*** 5.95***

(0.80) (0.48) (0.80) (0.49) Party ID: Independent 3.67*** 3.06*** 3.75*** 3.18***

(0.46) (0.36) (0.46) (0.36) Education 0.21*** 0.16***

(0.04) (0.05) Age 0.01* 0.02***

(0.01) (0.01) Female 0.15 -0.20

(0.17) (0.18) Constant -0.81*** 1.90*** -4.27*** -1.27*** -5.72*** -2.70***

(0.23) (0.18) (0.53) (0.40) (0.67) (0.59)

Observations 1,456 1,456 1,412 1,412 1,405 1,405

Pseudo R-squared 0.102 0.102 0.363 0.363 0.375 0.375 Standard errors in parentheses *** p<0.01, ** p<0.05, * p<0.1

The substantive importance of ideology is even clearer when estimating predicted

probabilities. For example, if a voter self-placement in the ideological scale is 0 (leftist), this

  16

voter has a probability of 0.21 to vote for the PRI but if the voter self-placement is 10 (right) the

probability increases to 0.68. In other words, there is an amount of change of 0.47 when ideology

changes from the minimum value to the maximum. In the case of the PRD the amount of change

is -0.64 and for the PAN is 0.17. As referred in the introduction of this paper, it is relevant that

the PRI, and not the PAN, benefited from rightist voters, which is a big change when compared

with previous presidential and legislative elections when the PAN tend to receive most of their

votes from this part of the electorate.

IDEOLOGY (range 0-10): Changes in Probabilities for Vote choice (DV)

Average Change PAN PRD PRI

Min->Max* 0.43 0.17 -0.64 0.47 *Discrete change of ideology: from its minimum to its maximum

In the following lines I will evaluate if the effect of ideology on vote choice is stronger

among voters that are aware of the ideological differences between major political parties.

0.2

.4.6

.81

0 2 4 6 8 10Ideological scale

PAN PRI PRD

Predicted Probabilities

2012: Ideology and Vote Choice

  17

Regarding the pair PRI v. PRD, in the following model I evaluate the interaction between

IDEOLOGY and IDEOLOGICAL DIFFERENCE which is the absolute difference between the

perceived ideological position of the PRI and the perceived ideological position of the PRD. In

other words, I will evaluate the conditional effect of perceived ideological differences between

parties on the electoral impact of ideology.

 Logistic regression

DV: Vote choice (PRI v. PRD)

(1) (2) (3) (4)

Ideology (left-right) 0.30*** 0.23*** 0.32*** 0.27***

(0.06) (0.07) (0.04) (0.05) Ideological difference

|PRI-PRD| -0.10 (0.06)

-0.14* (0.08)

Ideology* Ideological difference |PRI-PRD|

0.02** (0.01)

0.02* (0.01)

Substantive Ideological difference PRI-PRD

-0.11** (0.05)

-0.10* (0.06)

Ideology* Substantive Ideological difference PRI-PRD

0.05*** (0.01)

0.05*** (0.01)

Party ID: PRI 2.21*** 1.80***

(0.49) (0.52) Party ID: PRD -3.58*** -3.26***

(0.49) (0.52) Party ID: Independents -0.92** -1.05***

(0.36) (0.39) Education -0.13** -0.16***

(0.05) (0.06) Age -0.02*** -0.02**

(0.01) (0.01) Female 0.08 0.17

(0.19) (0.21) Constant -1.45*** 1.03 -1.99*** 0.49

(0.37) (0.70) (0.28) (0.66)

Observations 1,018 981 1,018 981 Pseudo R-squared 0.202 0.438 0.370 0.523

Standard errors in parentheses *** p<0.01, ** p<0.05, * p<0.1    

In this regard, I find that the interaction is statistically significant to the 0.05% level

(model 1), and remains statistically significant now at the 0.1% level when controlling for

  18

additional variables (model 2). In other words, when the respondent perceives ideological

differences between the PRI and the PRD, ideology has a stronger impact on vote choice. The

substantive importance of perceived ideological differences between parties is even clearer in the

following graph. For example, the probability of voting for the PRI is stronger among rightists

voters if the respondents perceives ideological differences vis-à-vis the PRD.

When evaluating the interaction between IDEOLOGY and SUBSTANTIVE

IDEOLOGICAL DIFFERENCE I found stronger results, which are statistically significant at the

0.01% level. In other words, the probability of voting for the PRI among rightists voters is

stronger among respondents that are aware of the correct ideological position between the PRI

and the PRD (in other words, PRD at the left of the PRI), and the effect of ideology on vote

choice is stronger when the perceived ideological difference between both parties is larger5 (see

graph).

 

                                                                                                                   5 The largest possible difference is 10. If the respondent does not perceive any ideological difference between the two parties then |PRI-PRD| = 0.

0.2

.4.6

.81

Pr(V

ote=

PRI)

0 1 2 3 4 5 6 7 8 9 10

|PRI-PRD|=0 |PRI-PRD|=5

|PRI-PRD|=10

Absolute difference

0.2

.4.6

.81

Pr(V

ote=

PRI)

0 1 2 3 4 5 6 7 8 9 10

PRI-PRD=0 PRI-PRD=5

PRI-PRD=10

Substantive difference

PRI v. PRDAwareness of ideological differences

  19

Regarding the pair PAN v. PRD, I find stronger results. The interaction between

IDEOLOGY and IDEOLOGICAL DIFFERENCE is statistically significant to the 0.01% level

even when controlling for additional variables (model 1 and 2). In other words, when the

respondent perceives ideological differences between the PAN and the PRD, ideology has a

stronger impact on vote choice.

 Logistic regression

DV: Vote choice (PAN v. PRD)

(1) (2) (3) (4)

Ideology (left-right) 0.15** 0.13* 0.23*** 0.22***

(0.06) (0.08) (0.04) (0.05) Ideological difference

|PAN-PRD| -0.20** (0.08)

-0.18** (0.09)

Ideology* Ideological difference |PAN-PRD|

0.04*** (0.01)

0.04*** (0.01)

Substantive Ideological difference PAN-PRD

-0.25*** (0.05)

-0.17*** (0.06)

Ideology* Substantive Ideological difference PAN-PRD

0.08*** (0.01)

0.06*** (0.01)

Party ID: PRI -2.80*** -2.65***

(0.67) (0.72) Party ID: PRD -6.34*** -5.39***

(0.79) (0.80) Party ID: Independents -2.47*** -2.21***

(0.33) (0.36) Education 0.01 -0.04

(0.06) (0.06) Age -0.01 -0.01

(0.01) (0.01) Female 0.29 0.34

(0.22) (0.24)

Constant -1.46*** 1.19 -2.11*** 0.41

(0.43) (0.80) (0.28) (0.72)

Observations 712 690 712 690 Pseudo R-squared 0.233 0.448 0.415 0.534

Standard errors in parentheses *** p<0.01, ** p<0.05, * p<0.1

When evaluating the interaction between IDEOLOGY and SUBSTANTIVE

IDEOLOGICAL DIFFERENCE I also found strong results, which are statistically significant to

  20

the 0.01% level. The probability of voting for the PAN among rightists voters is stronger among

respondents that are aware of the correct ideological position between the PAN and the PRD (in

other words, PRD at the left of the PAN), and the effect of ideology on vote choice is stronger

when the perceived ideological difference between both parties is larger (see graph).

4. Conclusions

In this paper I found that voters’ ideological orientations on vote choice are stronger

when voters are aware of the ideological differences between parties. And the effect is stronger

when the perceived ideological difference is larger. This finding is relevant because it brings

attention to the specific conditions under which we should expect that ideology impacts voters’

electoral decision: when parties and candidates emphasize and take clearly distinct stands on

particular policy issues, and at the individual level, when citizens care about policy issues and

recognize party and candidate differences on them. It also confirms that in an increasingly

0.2

.4.6

.81

Pr(V

ote=

PAN

)

0 1 2 3 4 5 6 7 8 9 10Ideology

|PAN-PRD|=0 |PAN-PRD|=5

|PAN-PRD|=10

Absolute Difference

0.2

.4.6

.81

Pr(V

ote=

PAN

)

0 1 2 3 4 5 6 7 8 9 10Ideology

PAN-PRD=0 PAN-PRD=5

PAN-PRD=10

Substantive Difference

PAN v. PRDAwareness of ideological differences

  21

institutionalized party system, voters become aware of what major parties represent ideologically

and this information is relevant when choosing among political alternatives at election time.

5. References Beltrán, Ulises (2009), “Ideología y polarización en la elección del 2006”, Política y Gobierno, special

volume, pp. 176-198. Downs, Anthony (1957), An Economic Theory of Democracy, Nueva York, Harper. Erikson, Robert S., Michael MacKuen y James A. Stimson (2002), The Macro Polity, Cambridge,

Cambridge University Press. Lewis-Beck, Michael S., William G. Jacoby, Helmut Norpoth, and Herbert F. Weisberg. 2008. The American Voter Revisited. Ann Arbor, MI: University of Michigan Press. Moreno, Alejandro (1999a), “Ideología y voto: Dimensiones de competencia

política en México en los noventa”, Política y Gobierno, VI (1), pp. 45-81.

______ (1999b), “Campaign Awareness and Voting in the 1997 Mexican Congressional Elections”, Jorge I. Domínguez y Alejandro Poiré (eds.), The Transformation of Mexico’s Parties: Campaigns, Elections, and Public Opinion, Nueva York, Routledge.

______ (2003), El votante mexicano, México, Fondo de Cultura Económica. ______(2006) Changing ideological dimensions of party competition in Mexico, 1900-2006, MIT

Department of Political Science Colloquium, November 30, 2006. Long, J. Scott and Jeremy Freese (2005) Regression Models for Categorical Outcomes Using Stata. Second Edition. College Station, TX: Stata Press. Lupia, Arthur y Matthew D. McCubbins (1998), The Democratic Dilemma: Can Citizens Learn what they

Need to Know? Political Economy of Institutions and Decisions, Cambridge y Nueva York, Cambridge University Press.

Lupia, Arthur, Matthew McCubbins y Samuel L. Popkin (eds.) (2001), Elements of Reason: Cognition,

Choice and the Bounds of Rationality, Cambridge University Press. Page, Benjamin I. y Robert Y. Shapiro (1992), The Rational Public, Chicago, University of Chicago

Press. Popkin, Samuel L. (1994), The Reasoning Voter: Communication and Persuasion in Presidential

Campaigns, 2nd. ed., Chicago, University of Chicago Press. Sniderman, Paul, Richard A. Brody, y Phillip Tetlock (eds.) (1991), Reasoning and Choice: Explorations

in Political Psychology, Cambridge, Cambridge University Press.

  22

Appendix

Table A1: Multinomial logistic regression DV: Vote choice (PAN v. PRI)

1997 2000 2003 2006 2009 2012 Ideology 0.08** 0.03 -0.03 -0.10** -0.13*** -0.01 (0.04) (0.03) (0.03) (0.05) (0.04) (0.04)

Party ID: PAN -7.07*** -4.01*** -4.96*** -5.39*** -5.19*** -5.58*** (0.81) (0.36) (0.39) (0.47) (0.32) (0.48)

Party ID: PRD -3.10*** -2.57*** -3.43*** -1.64* -2.54*** -3.12*** (0.73) (0.59) (0.67) (0.95) (0.59) (0.80)

Party ID: Independents -3.28*** -2.22*** -2.90*** -3.10*** -3.02*** -3.75*** (0.39) (0.21) (0.35) (0.31) (0.28) (0.46)

Education -0.20*** -0.12*** -0.08* -0.08 -0.02 -0.21*** (0.06) (0.04) (0.05) (0.06) (0.04) (0.04)

Age -0.24 -0.09 0.01 -0.00 0.00 -0.01* (0.14) (0.11) (0.01) (0.01) (0.01) (0.01)

Female 0.28 0.21 -0.19 0.03 -0.26 -0.15 (0.24) (0.19) (0.20) (0.24) (0.17) (0.17)

Constant 4.10*** 1.64*** 3.44*** 3.20*** 4.54*** 5.72*** (0.74) (0.53) (0.62) (0.72) (0.58) (0.67)

Observations 970 924 864 974 1,347 1,405 Pseudo R-squared 0.432 0.283 0.362 0.459 0.417 0.375

Standard errors in parentheses *** p<0.01, ** p<0.05, * p<0.1

  23

Table A2: Multinomial logistic regression DV: Vote choice (PAN v. PRD)

1997 2000 2003 2006 2009 2012

Ideology -0.08** -0.13*** -0.12*** -0.16*** -0.26*** -0.34*** (0.03) (0.04) (0.04) (0.04) (0.05) (0.04)

Party ID: PAN -3.67*** -0.82 -1.66** -2.64*** -3.76*** -3.25*** (0.69) (0.64) (0.66) (0.48) (0.63) (0.64)

Party ID: PRD 3.28*** 3.68*** 3.25*** 4.76*** 3.07*** 2.83*** (0.65) (0.60) (0.72) (0.81) (0.60) (0.82)

Party ID: Independents 0.03 0.82 0.37 -0.04 -0.76* -0.57 (0.48) (0.54) (0.61) (0.39) (0.40) (0.57)

Education -0.20*** -0.04 -0.06 0.07 0.06 -0.05 (0.05) (0.05) (0.06) (0.05) (0.06) (0.05)

Age -0.37*** -0.01 0.01 -0.01 0.02* 0.01 (0.13) (0.14) (0.01) (0.01) (0.01) (0.01)

Female -0.34 -0.04 -0.15 -0.19 0.08 -0.34* (0.22) (0.24) (0.25) (0.21) (0.24) (0.19)

Constant 2.99*** -1.37* -0.07 1.05 0.74 3.02*** (0.73) (0.80) (0.86) (0.68) (0.80) (0.78) Observations 970 924 864 974 1,347 1,405 Pseudo R-squared 0.432 0.283 0.362 0.459 0.417 0.375

Standard errors in parentheses *** p<0.01, ** p<0.05, * p<0.1

  24

Table A3: Multinomial logistic regression DV: Vote choice (PRI v. PRD)

1997 2000 2003 2006 2009 2012

Ideology -0.16*** -0.15*** -0.09** -0.06 -0.12*** -0.33*** (0.03) (0.04) (0.04) (0.04) (0.04) (0.03)

Party ID: PAN 3.41*** 3.18*** 3.30*** 2.74*** 1.42** 2.33*** (0.92) (0.69) (0.61) (0.57) (0.60) (0.47)

Party ID: PRD 6.38*** 6.25*** 6.67*** 6.41*** 5.62*** 5.95*** (0.55) (0.73) (0.69) (0.66) (0.42) (0.49)

Party ID: Independents 3.31*** 3.05*** 3.27*** 3.06*** 2.26*** 3.18*** (0.33) (0.54) (0.53) (0.34) (0.31) (0.36)

Education -0.00 0.07 0.02 0.15** 0.08 0.16*** (0.05) (0.06) (0.06) (0.06) (0.06) (0.05)

Age -0.13 0.09 -0.00 -0.00 0.02* 0.02*** (0.13) (0.17) (0.01) (0.01) (0.01) (0.01)

Female -0.62*** -0.25 0.04 -0.21 0.35 -0.20 (0.22) (0.27) (0.25) (0.26) (0.22) (0.18)

Constant -1.11* -3.01*** -3.50*** -2.15*** -3.80*** -2.70*** (0.61) (0.87) (0.81) (0.73) (0.69) (0.59)

Observations 970 924 864 974 1,347 1,405 Pseudo R-squared 0.432 0.283 0.362 0.459 0.417 0.375

Standard errors in parentheses *** p<0.01, ** p<0.05, * p<0.1

  25

05

1015

Perc

ent

0 1 2 3 4 5 6 7 8 9 10Ideological difference

O: no difference; 10: largest difference

Ideological difference: PRI v. PRD

05

1015

Perc

ent

-10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10Ideological difference

negative: incorrect ideological difference; positive: correct ideological difference

Substantive ideological difference: PRI v. PRD

  26

05

1015

Perc

ent

0 1 2 3 4 5 6 7 8 9 10Ideological difference

O: no difference; 10: largest difference

Ideological difference: PAN v. PRD

05

1015

Perc

ent

-10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10Ideological difference

negative: incorrect ideological difference; positive: correct ideological difference

Substantive ideological difference: PAN v. PRD