Dependent variables

In this analysis, the main dependent variables are attitudinal and self-reported behavioural measures. The three dependent variables used are the only measures directly relating to economic and redistributive issues in the survey. They are:

1. (1) Inequality attitude: MPs rate agreement (on a 1–5 scale from strongly disagree to strongly agree) with the statement: ‘Larger income differences are needed as incentives for individual effort.’

2. (2) Role of government in the economy attitude: MPs rate agreement (on the same scale) with the statement: ‘Government should play a smaller role in the management of the economy.’

3. (3) Contact with workers’ organizations: MPs answer the question, ‘In your role as a Member of Parliament, how often in the last year have you had contact with … workers’ organizations and trade unions’ (on a 1–5 scale ranging from ‘(almost) no contact’ to ‘at least once a week’). Note that the question specifies that it is about contact in their role as MPs and so should exclude contact in social or other capacities, if legislators observe this caveat in their responses.

Both legislators’ attitudes and their behaviour merit attention. Previous research indicates that legislators’ attitudes may be a key link in the causal chain connecting class and policy outcomes. For example, when US legislators’ opinions were added as a control variable in Carnes’s (Reference Carnes2013) regression models, the substantial class-based differences in Congressional voting records disappeared. Furthermore, the practical importance of the attitude measures is reinforced by legislators’ responses to two relevant questions in the Comparative MP Survey data. First, nearly 70% of legislators in the sample say that if an MP's personal opinions conflict with those of voters, that MP should follow his or her personal opinion. Similarly, 47% say an MP's own opinion should also take precedence over their party's position. Thus, a large share of the surveyed legislators apparently believe that their own opinions are important in their role as MPs, even trumping those of their voters and parties. At the same time, it should be acknowledged that the variables on attitudes described above each rely on responses to a single question, using a simple five-point scale from strongly disagree to strongly agree, which cannot fully capture the nuance of respondents’ attitudes on these questions.Footnote ³ In turn, an important limitation of the behaviour measure is that it is self-reported rather than directly observed. However, respondents remain anonymous in the survey, meaning there is little incentive to misreport intentionally. The findings on this self-reported behaviour measure complement more direct measures in the literature.

Since more experienced and powerful MPs are more likely to influence party positions and policy outcomes (and therefore their attitudes and behaviour may be of more practical significance), I also run additional versions of my main regression models on relevant subsamples of such legislators (e.g. those who have previously held elected office, sponsored at least one bill or held at least one parliamentary leadership position).

Explanatory variables

Legislators’ occupations prior to taking office are used as the operationalization of class, which is the key independent variable. Sociological literature supports defining class in terms of occupation (Kalmijn and Kraaykamp Reference Kalmijn and Kraaykamp2007; Manza et al. Reference Manza, Hout and Brooks1995; Weeden and Grusky Reference Weeden and Grusky2005), which marks distinct perspectives and lived experiences, and this is consistent with recent research on the substantive representation of class (Carnes Reference Carnes2013; Carnes and Lupu Reference Carnes and Lupu2014; O'Grady Reference O'Grady2018). Empirical work on the US finds that occupational class predicts legislators’ voting behaviour, but family background, education and income do so more poorly, or not at all (Carnes Reference Carnes2013).

The data set includes an open-ended text field describing the legislator's occupation, which Deschouwer and colleagues (Reference Deschouwer, Depauw, André, Deschouwer and Depauw2014: 8) explain they have ‘collected from official sources such as the parliamentary websites and “who's who” guides’ and refers to their occupation prior to election as an MP. I have coded these descriptions into a set of 10 occupational categories, adapting the categorization scheme used by Carnes (Reference Carnes2013) and Carnes and Lupu (Reference Carnes and Lupu2014).Footnote ⁴ For example, the ‘business’ category includes occupations such as business owners, managers, bankers and consultants and serves as the omitted base category in the regression models described below. The ‘worker’ category includes manual, service industry, clerical and union staff jobs. The ‘service-based professional’ category includes teachers, nurses, social workers and community organizers. Notably, the findings are robust to multiple checks on the coding scheme, including replication in a second data set with differently structured occupation data, described in a later section of the article.Footnote ⁵

There is a correlation between class and party type, but one that is far from perfect. Workers tend to be found in left parties, but they also have a substantial presence in right parties. Conversely, businesspeople are found in left parties, though they are predominantly in right parties.Footnote ⁶ This variation of class within party types provides an opportunity to separate empirically the influence of class from that of party.

Using a similar categorization scheme, Carnes (Reference Carnes2013) and Carnes and Lupu (Reference Carnes and Lupu2014) found that business sector legislators had among the most right-wing attitudes and behaviours on redistributive issues, while those from working-class occupations were the most left-wing, followed by service-based professionals.

In terms of controls, a key control variable indicates whether the legislator is a member of a left-leaning political party. This is based on an expert classification of parties in the PARTIREP data set, which includes 12 categories that I have collapsed into a single ‘left party’ dummy.Footnote ⁷ As a robustness check, I also used an alternative left party control (based on MPs’ self-reports about their party's ideological left–right position) both in dummy and continuous form, and the results are substantively similar. Other legislator-level control variables available in the data set include age, gender and education. Education is not included as a control variable in the main model specifications but is included in later robustness checks.Footnote ⁸ Age and gender are included as the available personal-level controls in the data set and because of their plausible correlation with the outcome variables. Other control variables used include dummies for each country and parliament.

Model specification

To assess the main relationship between the descriptive and substantive representation of class, I estimate linear regression models of the form:

$$OutcomeVariable_{ij} = \beta _{1- 10}Occupation_{ij} + \beta _{11}( LeftParty_{ij}) + \beta _{12}( Female_{ij}) + \beta _{13}( Age_{ij}) + \gamma _k + \epsilon _{ij}$$

where Occupation refers to the occupation category of the legislator i in parliament j (which includes both national and subnational parliaments). LeftParty indicates membership of an identifiably left-leaning political party. Female and Age refer to the gender and age of the politician, respectively. Country fixed effects are represented by γ and ε is the error term. Standard errors account for potential correlations within parliaments (clustered at the parliament level). The vector of individual-level outcome variables includes: attitude on inequality, attitude on government role in the economy, and self-reported contact with workers’ organizations.

For each outcome variable, results are shown for three specifications: (1) a simple regression of occupation on the outcome variables without controls (but with country fixed effects and standard errors clustered by parliament); (2) a model with control variables (the baseline specification); and (3) a model with controls and that also weights observations to equalize the influence of countries and regional/national parliaments.Footnote ⁹ In each model, the business occupation category is the omitted reference category for the independent variable.Footnote ¹⁰ Note again that controlling for party type means that the coefficient for legislators’ class should be taken as a lower bound estimate, since politicians with different occupations already tend to sort into different types of parties.

Because the dependent variable is strictly speaking ordered rather than continuous, ordered logistic regression models have also been run as a robustness check. Additional specifications, including a multilevel model with legislators nested within parliaments, were run and give substantively similar results.Footnote ¹¹

Legislators’ attitudes

Table 1 shows the results for each model seeking to examine the relationship between occupational class and legislators’ attitudes (separately for inequality and government intervention in the economy). As described above, these attitude variables are on a 1–5 scale, with higher values corresponding to more right-wing attitudes.

Table 1. Regression Models on Legislators’ Attitudes

Notes: Standard errors in parentheses. Higher coefficient indicates more right-wing attitude. The ‘no occupation information’ category, country dummies and coefficients for controls (except party) are not shown here for ease of presentation. See Table A4 in the Online Appendix for full regression results. +p < 0.10; *p < 0.05; **p < 0.01.

Each model shows substantively and statistically significant (p < 0.05) differences in the attitudes of business sector legislators and at least three other occupational class backgrounds. All occupation coefficients across the models trend in the expected direction, with business sector legislators displaying attitudes on economic issues to the right of their counterparts from other backgrounds.

Results from Models 2 and 5 (with controls, unweighted) are depicted in Figure 1. These can be considered baseline specifications for the two attitudinal outcome variables. Since my interest is in detecting the impact of legislators’ class at an individual level (as opposed to drawing inferences about a representative set of parliaments), the unweighted models are appropriate baselines.

Figure 1. Estimated Class-Based Differences in Legislators’ Attitudes

Note: Lower scores correspond to more economically left-wing attitudes. Dots are model coefficients and lines are 95% confidence intervals. Business is the omitted reference category for occupation.

First, consider the inequality attitude outcome variable. The baseline Model 2 results show negative and statistically significant (p < 0.05) coefficients for four categories, meaning each of these occupation categories displays more anti-inequality attitudes compared with legislators from the business sector. The largest differences for this outcome variable are between legislators in the business sector, on the one hand, and service-based professionals, workers and ‘other white-collar’ on the other hand.

One way to think about the substantive importance of these differences is by comparing it to the coefficient for being in a left party. This is a natural point of comparison, since political parties function as the key political aggregators of class conflict. Left-party legislators are generally expected to display greater concern about inequality and more openness to government intervention in the economy. Indeed, such economic questions are usually considered to be the most basic characteristic of the left–right political spectrum.

The results show that occupations predict differences in legislator attitudes that are on a comparable scale to differences associated with party identity. For example, a service-based professional displays significantly more opposition to inequality compared with a business sector legislator, and the coefficient size is about 40% of being in a left party. In terms of inequality attitudes, the coefficient for being a worker versus a business sector legislator is over 25% that of being in a left party.

In Model 3 (weighted), the differences between business sector legislators and the same three occupation categories remain substantively and statistically significant. This model provides assurance that the results are robust to levelling out the influence of the different parliaments in the sample.

Next, consider the second attitude outcome variable, which relates to government intervention in the economy. In Model 5 (controls, unweighted), workers and service-based professionals (as well as farmers and those in politics and law enforcement) are substantively and significantly (p < 0.05) more favourable to government's role in the economy than business sector legislators.

Compared against the coefficient for party type on this attitude, the observed differences by occupational class are substantial. Left-party legislators are, as expected, more favourable to government intervention in the economy than legislators from other parties. The coefficient size of being a worker or service-based professional (as opposed to from the business sector) is about 20% that of being in a left party. For farmers, the coefficient is even larger, at over 30% that of being in a left party. In Model 6 (weighted), much the same pattern of coefficients holds, though the coefficient for the worker category is reduced and loses significance.

Overall, the observed differences by legislators’ class are somewhat more pronounced regarding their attitudes on inequality than their attitudes on government's role in the economy. This makes theoretical sense, since the issue of economic inequality is arguably more intrinsically bound up with class than government's role in the economy (though both are clearly linked).

The results presented can be taken as lower bound estimates of the coefficient for class in an important sense. To the extent that prospective legislators sort into left and right parties because they hold beliefs shaped by their class backgrounds, the models with party controls would tend to underestimate the coefficient for class (with some of the influence of class appearing in the left party coefficient). Therefore, I also report results for Models 1 and 4, which exclude controls. These models show much larger coefficient sizes for most occupations compared with the business sector (coefficients more than double in the case of workers) and would represent an upper bound estimate of the relationship between legislators’ class and their attitudes.

The results of Models 1 through 6 bring to bear new evidence of an empirical link between the descriptive and substantive representation of class. They are consistent with the theory that the occupational class of legislators affects their economic policy attitudes across a broad set of developed countries.

To summarize, business sector legislators tend to be more favourable to inequality and less favourable to government intervention in the economy than other occupational backgrounds and particularly compared with workers and service-based professionals. These coefficient sizes are comparable to, though smaller than, those of party type. These findings are consistent with the US-based research of Carnes (Reference Carnes2013: ch. 4), which showed that legislators from business backgrounds had among the most right-wing attitudes, and workers and service-based professionals had the most left-wing attitudes.

Legislators’ behaviour

The Comparative MP Survey also includes a behavioural dependent variable of interest: self-reported levels of contact with workers’ organizations and trade unions. Note that, as mentioned above, the question specifies that this refers only to contact in their role as MPs (and so should exclude contact in social or other capacities). This allows us to evaluate the prediction that legislators’ class will help shape their behaviour as representatives. Given the well-recognized role of unions in pressuring governments to adopt solidaristic and pro-worker policies (Hooghe and Oser Reference Hooghe and Oser2016; Korpi Reference Korpi2006), contact with these organizations is of substantive importance.

In Model 8 (with controls), there is a significant relationship between legislators’ class and their contact with workers’ organizations (see Table 2). Specifically, business sector legislators are much less likely than workers (the only significantly different category) to report higher levels of contact with these organizations. The coefficient for party type again provides a helpful point of comparison for gauging the relative importance of class. Given the well-established links between many social democratic parties and the labour movement, we expect and observe that legislators from left parties have more contact with workers’ organizations than those from other types of parties.

Table 2. Regression Models on Legislators’ Contact with Workers’ Organizations

Notes: Standard errors in parentheses. Higher coefficient indicates more contact with workers’ groups. See Table A5 in the Online Appendix for full regression results. +p < 0.10; *p < 0.05; **p < 0.01.

The magnitude of the difference between business legislators and workers is large, amounting to a little more than 50% the coefficient for being in a left party compared with another party type. In the model with the observations weighted to equalize countries and regional/national parliaments (Model 9), the coefficient is just under 50% of that for party, while in the no-controls specification (Model 7), the coefficient increases substantially relative to its size in the baseline model.

In short, the results show a significant class-based difference in legislators’ contact with workers’ organizations and trade unions, with working-class legislators making higher levels of contact than their business-class counterparts. When we examined attitudinal outcomes in the previous section, service-based professionals were at least as different as workers from their counterparts in business, but here it is only workers who appear to be distinct.

Thus, for this behavioural measure, the main occupational ‘fault line’ for contact with workers’ organizations and trade unions is between workers and legislators from other occupational categories. Indeed, supplementary analysis with workers as the omitted reference category shows that workers are significantly different from five other occupational categories by this contact measure.Footnote ¹² Working-class legislators are therefore the only category consistently distinct from business-class legislators across all three of the attitudinal and behavioural outcome variables.

Institutional moderators

As a cross-national, multi-parliament data set, the Comparative MP Survey also offers an opportunity to examine potential moderators of the influence of legislators’ class, including electoral institutions. A recent study of the link between gender and the representation of women's issues, which focused on the moderating effects of electoral institutions, offers a useful framework for examining institutional moderators in the context of class (Lore Reference Lore2016). Lore found that institutional features such as open party lists, local nominations, and division of powers systems heighten the differences between men and women in the substantive representation of women's issues.

According to Grace Lore's (Reference Lore2016) theory of ‘incentives for unincorporated representation’, each of these three institutional characteristics increases the incentives for competition between individual legislators within parties. The converse of these features – closed lists, centralized nominations, and the fusion of powers – are expected to dampen individual-level differences. Open party lists and local nomination battles straightforwardly imply greater competition between prospective legislators of the same party. Perhaps less obvious is how division of powers systems, unlike fusion of powers systems, increase intra-party competition between legislators. As Lore (Reference Lore2016) outlines, division of powers systems are characterized by weaker party discipline relative to parliamentary systems with the fusion of powers, which means more opportunities for differentiation between legislators in the same party. Lore's framework is an elaboration of John Carey and Matthew Shugart's (Reference Carey and Shugart1995) theory of personal versus party votes.

For the present article, an exploratory analysis was conducted to examine whether variation in these electoral institutions moderates the relationship between legislators’ class and both their attitudes and behaviour.Footnote ¹³ This analysis makes use of institutional variation across the national and subnational jurisdictions covered in the Comparative MP Survey. Specifically, interactions between institutional features and occupation are added to the main model specification used above.

In brief, the analysis suggests that variation in electoral institutions does indeed play a role in moderating the practical importance of class representation. Certain institutional features appear to magnify class-based individual differences between legislators, possibly by the theorized mechanism of increasing incentives for intra-party competition. Specifically, the results show that open lists and division of powers systems (compared with closed lists and fusion of powers systems, respectively) are associated with larger class-based differences between legislators on the attitude and behaviour outcome variables examined in this article. No such moderating relationship is observed when interacting the third institutional feature of local nominations. Further theoretical and methodological context for this analysis, as well as more detailed empirical results, are provided in the Online Appendix.

Political culture of a country or region

One concern we might have is that some jurisdictions have, overall, a more economically left-wing political culture than others. In such jurisdictions, voters may be more likely to elect legislators of certain class backgrounds, such as workers (and less likely to elect legislators of other backgrounds, such as the business sector). If so, workers in the sample would be more likely to ‘show up’ in left-wing jurisdictions. Thus, these worker legislators may exhibit more economically left-wing attitudes and behaviour simply as a reflection of their jurisdiction's political culture. This could lead to the observation of a spurious relationship between class and these measures.

The analyses reported above account for political culture in a few ways. The main models include a ‘left party’ variable, so there is a clear control for political ideology. The main models with controls also include dummy variables for each country that control for characteristics specific to that jurisdiction, such as a left-wing political culture. Furthermore, as an additional check, when country dummies are replaced with parliament dummies, the observed differences by class remain.Footnote ¹⁴

In addition, we can control for a parliament's ‘political culture’ by taking the average class attitudes of all legislators within the parliament (using an index variable averaging attitudes on the inequality and government intervention in the economy questions). When this new variable is added as an additional control in the main models, the observed differences by class still hold for all three dependent variables.Footnote ¹⁵ The differences by class also hold if controls are included for the parliament average of legislators’ self-assessed position on the left–right spectrum, as well as the parliament average for a variable rating how important legislators believe it is to ‘represent employees’ in their role as parliamentarians.

Finally, in the Comparative MP Survey legislators also assess how they believe the electorate is positioned on the left–right ideological spectrum. When we take the average of this assessment of the electorate's left–right position (by all legislators in a parliament) and use it as a control in the main model, the relationship between legislators’ class and their attitudes and behaviour still holds.Footnote ¹⁶

Constituents’ preferences at the district level

The previous subsection dealt with controlling for potential confounds due to political culture at the country and regional levels. In addition, within electoral districts it could be the case that legislators of a certain class tend to be elected by voters with a distinct set of policy preferences. Legislators may then reflect those voters’ preferences in their attitudes and behaviour. For example, a left-wing district may be more likely both to elect a worker and to demand left-wing policies. Thus, we might be concerned that constituents’ preferences may be a confounding variable, driving both our independent variable (legislators’ class) and our dependent variables (legislators’ attitudes and behaviour).

Since the data set does not include information on the characteristics of voters within districts (and legislators are anonymized), it is not possible to test this possibility directly. However, most of the observations are in proportional representation systems, which are characterized by weaker links between constituencies and individual legislators. When the sample is explicitly limited to legislators in proportional systems and excludes those elected in single-member districts, the relationship between legislators’ class and their attitudes and behaviour persists. In addition, when I limit the sample to legislatures with higher district magnitudes (greater than 15, for example), thereby loosening the link between constituency characteristics and individual legislators, the observed differences by class persist on all three dependent variables.Footnote ¹⁷

Furthermore, suppose constituents’ preferences were acting as a confound driving both the independent variable (occupation) and outcome variables (attitudes and behaviour). We should then reflect on why, for example, left-wing voters would tend to elect more workers in the first place. If voters see legislators’ class as a credible signal of the policies they will represent, then this is precisely consistent with the idea that class has a bearing on legislators’ policy attitudes and behaviour.

Alternative outcome variables

We still may be concerned at the possibility of a spurious relationship between legislators’ occupation and their attitudes and behaviour, due to confounds not already addressed above. Another way of checking whether the observed relationships are spurious is to swap out the dependent variables for a set of ‘placebo’ outcome variables. These are variables that we would not theoretically expect to be as strongly driven by legislators’ class as the core economic issues addressed in the main outcome variables, which relate directly to class (though some differences would not be unexpected).

Three additional non-class-focused ‘political issues’ questions were put to legislators in the Comparative MP Survey, directly alongside the two questions that serve as the main outcome variables. They ask MPs to rate their agreement (on a 1–5 scale) with the following statements:

• ‘People who break the law should be given stiffer sentences.’

• ‘Immigrants should be required to adapt to the customs of our country.’

• ‘Government should make sure that films and magazines uphold moral standards.’

For all three of these questions, distinctly fewer occupation categories exhibited a significant difference than they did for the main attitude dependent variables.Footnote ¹⁸ For example, working-class legislators are not significantly different from those from the business sector on any of these questions. The weaker class link between legislators’ occupations and these alternative outcome variables is consistent with expectations and strengthens confidence in the main results. There was a significant difference between business sector professionals and at least one other occupation category for each of these questions. The presence of some differences is not surprising, given that classes do think differently about social issues such as these. We would also expect between one and two of the coefficients across these three alternative outcome variables to be significant by chance.

In addition, I can examine an alternative dependent variable that I do expect to be strongly related to class (i.e. not another placebo variable): legislators’ self-placements on the ideological left–right spectrum (on a scale from 1 to 10). Consistent with expectations, workers and service-based professionals (indeed all but one occupation category) clearly place themselves further left on the ideological spectrum than legislators from the business sector. Notably, this class-based difference in ideology is observed despite a left party dummy variable still being included in the model as a control.

Subsample of experienced and influential MPs

Another concern we might have about the reported results is that the attitudes and behaviour of many individual MPs may not be reflected in actual policy outcomes or party positions (for example, their influence may be blunted by party discipline). If so, the results may be of less practical importance. While we cannot directly test for this, we can observe whether the relationship between legislators’ class and their attitudes and behaviour holds among a subsample of relatively experienced and influential MPs, whom we may expect to exert greater influence on policy outcomes and party positions.

To examine this possibility, analyses have been run on three different subsamples of MPs: those who have previously held elected office, those who have sponsored at least one bill and those who hold at least one parliamentary leadership position (such as committee chair). Despite much smaller sample sizes, the observed differences by legislators’ class persists for both the attitude dependent variables (inequality and size of government) and the behaviour variable (contact with trade unions). This holds for the three subsamples of MPs across the three dependent variables, with a loss of significance in only two cases (one of which remains significant at the p < 0.1 level).Footnote ¹⁹

Testing class differences using a second data set

As a further test of the relationships observed in the Comparative MP Survey, a second data set of legislative candidates was used: the Comparative Candidate Survey (CCS 2016). The CCS analysis conducted includes candidates and their occupations and attitudes for seven European countries for parliamentary elections between 2005 and 2013.Footnote ²⁰

A particularly useful feature of the CCS data set is that the occupation variable comes pre-coded using a variation on the International Standard Classification of Occupations (ISCO) system. In contrast, the Comparative MP Survey provided raw, open-ended descriptions of the legislators’ occupations, which I had to interpret and code from scratch. To analyse the CCS data, I set rules to assign the standardized ISCO occupation codes from the CCS data to a set of categories similar to my main occupation categorization scheme (to yield an analysis as comparable as possible). Because the ISCO codes in CCS are at a relatively high level of abstraction, it was not possible to map onto exactly the same categories. But it is nonetheless possible to compare business sector candidates to a set of occupation categories similar to those in the Comparative MP Survey analysis.

The CCS data replicate the finding above that legislators’ class predicts their attitudes about inequality and government intervention in the economy (see Figure 2). This helps provide assurance that the main findings are not a result of idiosyncratic features of my coding work on the Comparative MP Survey data.

Figure 2. Estimated Class-Based Differences in Candidate Attitudes (CCS data)

Note: Lower scores correspond to more economically left-wing attitudes. Dots are model coefficients and lines are 95% confidence intervals. Business sector is the omitted reference category for occupation.

The CCS asked respondents questions on attitudes towards both inequality and government's role in the economy (though with somewhat different wording).Footnote ²¹ The results are shown in Figure 2 and confirm that candidates in the business sector held significantly more right-wing attitudes on inequality than most other occupation groups.Footnote ²² The largest difference, between the business sector and trades/skilled manual workers, is 28% of the coefficient size of being in a left party. Those candidates in the business sector were also significantly less favourable to government intervention in the economy than clerks and trades/skilled manual workers, and the coefficient size was 22% that of being in a left party.

The CCS also includes two additional class-relevant attitude questions. One is on globalization: ‘Globalization should be promoted’, and the other is on social security: ‘Providing a stable network of social security should be the prime goal of government.’

There is an even more stark relationship between candidates’ class and their responses on the globalization question. Business sector candidates are statistically and substantively more pro-globalization than all other occupation categories (except those designated as politicians; see Figure 3). Strikingly, being in a left party seems to have no significant influence on candidates’ attitudes towards globalization, which may reflect the broad pro-globalization consensus in major parties in Western countries in recent decades.

Figure 3. Estimated Class-Based Differences in Candidate Attitudes (CCS data)

Note: Lower scores correspond to more economically left-wing attitudes. Dots are model coefficients and lines are 95% confidence intervals. Business sector is the omitted reference category for occupation.

On the other additional question, candidates in the business sector are statistically and substantively less favourable to social security as a ‘prime goal’ of government than clerks and trades/skilled manual workers. The largest difference (between business sector and trades/skilled manual workers) amounts to about half of the coefficient size of being in a left party.

Finally, I ran a different set of models in which I categorized occupations only according to their original top-level ISCO codes (rather than mapping the codes into categories similar to my coding scheme for the main data set). Using this ‘unadjusted’ occupation coding scheme, the relationship between legislators’ class and their attitudes also remains significant and substantial.Footnote ²³

Additional robustness checks

Another concern we might have is that the results are sensitive to the estimation methods used. To address this possibility, a range of alternative specifications have been run for each of the three dependent variables. These additional specifications include using logistic regression instead of OLS, clustering standard errors by country instead of parliament, employing alternative control variables and constraining the analyses to certain subsamples. The results are substantively similar to those already presented. A more detailed description of these alternative specifications and their results is available in the Online Appendix.