Ideological congruence and representation

Close correspondence between the policy preferences of the people and the policy decisions made by their representatives is often considered a necessary component of representation (Dahl Reference Dahl1956). To Hanna Pitkin (Reference Pitkin1967), such substantive representation takes precedence over formalistic, symbolic or descriptive forms of representation as it has a bearing on the actions taken by representatives. As Matt Golder and Benjamin Ferland (Reference Golder, Ferland, Herron, Pekkanen and Shugart2018) note, empirical political scientists have operationalized substantive representation both as ideological congruence (Huber and Powell Reference Huber and Powell1994) and as policy responsiveness (Page and Shapiro Reference Page and Shapiro1983).Footnote ¹ Whereas responsiveness refers to a dynamic relationship between change in public opinion and change in policy output (e.g. Hobolt and Klemmensen Reference Hobolt and Klemmensen2008; Soroka and Wlezien Reference Soroka and Wlezien2010), congruence refers to a static assessment of the correspondence of public preferences and policy positions adopted or policy measures taken at a certain point in time (Golder and Ferland Reference Golder, Ferland, Herron, Pekkanen and Shugart2018: 215).

Ideological congruence is often studied at the aggregate level. The proximity between the mean or median ideological position in the citizenry is examined at different geographic levels of aggregation on the one hand, and the position of a single representative actor, such as a member of Congress (Miller and Stokes Reference Miller and Stokes1963), the position of a political party (Belchior Reference Belchior2013), the position of a national government (Huber and Powell Reference Huber and Powell1994; Powell and Vanberg Reference Powell and Vanberg2000) or the position of the entire legislature (see also Dolný and Baboš Reference Dolný and Baboš2015; Ezrow and Xezonakis Reference Ezrow and Xezonakis2011; Golder and Stramski Reference Golder and Stramski2010) on the other hand. As citizens hold preferences for multiple parties, a recent study has shown that assessing the extent to which government composition reflects the average party preferences of citizens holds great promise for studying the quality of representation at the aggregate level (Blais et al. Reference Blais, Guntermann and Bodet2017).

Such aggregate-level measures of ideological congruence between citizens and representatives or governments, however, mask whether the ideological placement of individual citizens is congruent with the chosen representative or party. By contrast, the literature on individual-level congruence examines the ideological agreement between those represented and those representing on the individual voter level. Some studies examine the congruence between a voter's preference and the position of a median party, legislature or government (Kim Reference Kim2009; Mayne and Hakhverdian Reference Mayne and Hakhverdian2017; Singh et al. Reference Singh, Lago and Blais2011). Such measures of congruence, however, cannot assess whether or under what conditions an individual voter is ideologically congruent with the representative or party she or he has voted for. In this vein, Richard Lau and David Redlawsk (Reference Lau and Redlawsk1997) examine the extent to which voters are able to ‘vote correctly’ – that is, their ability to choose a candidate who is closest to their ideological preferences and beliefs.

Congruence between a voter and the representative or party chosen can be thought of as the proximity between elector and elected in a spatial conception of the political space (Downs Reference Downs1957). As a result, selecting the best candidate is not a binary question of ‘correctness’, but a matter of degree: to what extent do the ideological characteristics of the voter match the representative of the party voted for? In this respect, research has started to focus on the correspondence between continuous measures of voters’ and representatives’ ideological preferences (Golder and Stramski Reference Golder and Stramski2010) – focusing on the consequences of incongruence for abstention voting (Lefkofridi et al. Reference Lefkofridi, Giger and Gallego2014), the relationship between congruence and voters’ satisfaction with democracy (Dahlberg and Holmberg Reference Dahlberg and Holmberg2014; Stecker and Tausendpfund Reference Stecker and Tausendpfund2016) or the effect of party identification and political sophistication on congruence (Boonen et al. Reference Boonen, Pedersen and Hooghe2017). To assess the consequences of ballot structures for the quality of representation we adopt this individual-level approach to congruence in this study.

Electoral systems and individual-level congruence

As the supply of political parties increases, the easier it becomes for voters to vote in line with their ideological preferences. The number of relevant parties a voter can choose from is largely determined by the ‘permissiveness’ of electoral institutions (Shugart and Taagepera Reference Shugart, Taagepera, Herron, Pekkanen and Shugart2018). Higher district magnitude and greater assembly size broaden voters’ range of relevant choice as parties gain parliamentary representation more easily. As such, while very small district magnitude in single-member plurality (SMP) systems offers voters a relatively small number of relevant parties to choose from, proportional representation (PR) systems with high district magnitude produce ballots with a higher number of viable party choices. For example, Israel's and the Netherlands’ de facto nationwide electoral districts – the district magnitude equals the assembly size – make these countries’ electoral systems as permissive as is possible (Shugart and Taagepera Reference Shugart, Taagepera, Herron, Pekkanen and Shugart2018).

Yet, it has been prominently argued in the literature that the permissiveness of an electoral system comes at the cost of both greater ideological polarization and greater government instability (Dalton Reference Dalton2008). More permissive electoral systems are argued to have centrifugal tendencies as ideologically extreme parties are more likely to achieve parliamentary representation, while less permissive systems produce centripetal incentives (Cox Reference Cox1990). Ideological polarization among parties, or average party extremism, is moreover associated with lower satisfaction with democracy (Ezrow and Xezonakis Reference Ezrow and Xezonakis2011). At the same time, it is argued that permissive electoral systems produce ideologically diverse governing coalitions which can inhibit effective government (Farrell Reference Farrell2011). The 2017 Dutch parliamentary election, in which 13 parties entered parliament and four parties were needed for a governing majority, is a case in point. Ideological diversity in government, moreover, negatively affects citizens’ perceptions of government performance (Singh and Thornton Reference Singh and Thornton2016). Furthermore, in comparison to systems with a higher party concentration, the link between government formation and a vote choice is weaker in systems that require a multiplicity of coalition parties. Unsurprisingly, therefore, coalition governments with a higher number of parties have more difficulty in being responsive to their voters (Ferland Reference Ferland2018).

In sum, the literature suggests that an increase in parties due to permissive electoral rules comes with a trade-off. Whereas a large party system may improve the congruence between a voter and her vote, coalition government stability and responsiveness become weaker.

Ballot structures and expressive voting

We posit that there is another institutional characteristic of electoral systems that may improve voter–vote congruence: the ballot structure (Gallagher and Mitchell Reference Gallagher, Mitchell, Herron, Pekkanen and Shugart2018). Ballot structures vary in their expressiveness. Expressiveness refers to the degree to which a voter may distribute his or her electoral strength over multiple options. Categorical ballots offer the smallest degree of expressiveness: the ballot forces a voter to throw her entire electoral strength behind one party or candidate (Rae Reference Rae1971). That said, flexible and open-list categorical ballots do allow voters to express their preference for a specific candidate (André et al. Reference André, Wauters and Pilet2012; Renwick and Pilet Reference Renwick and Pilet2016). Ordinal ballots are more expressive as they allow a rank-ordering of parties or candidates. Dividual ballots allow voters to divide their votes among more than one party or candidate. For instance, with ‘split-tickets’ in mixed-member electoral systems, voters can vote for different parties with their two votes. In ‘panachage’ systems, moreover, voters may distribute a number of preference votes among candidates of more than one party (Gallagher and Mitchell Reference Gallagher, Mitchell, Herron, Pekkanen and Shugart2018).

An open question in the literature is how voters distribute their electoral strength under non-categorical, expressive ballots. A straightforward expectation is that voters distribute their ‘electoral strength’ as they would vote under categorical ballots: They aim to minimize the distance between their own preferences and the preferences as reflected by their vote choice. In other words, voters opt for the choice that is located closest to them on a hypothetical political landscape (Downs Reference Downs1957). Jack Blumenau et al. (Reference Blumenau2017), for instance, found that voters voting under open-list systems are willing to abandon their party of choice to vote for an opposing party's candidate standing closer to their own preferences. In addition, recent research indicates that in mixed-member systems voters may use their two votes to express a more nuanced electoral choice (Plescia Reference Plescia2017; Riera and Bol Reference Riera and Bol2017). These observations strongly suggest that voters vote more expressively when so enabled by the electoral rulebook.

The assembly ballot

Collective decisions affecting self-determination should include those affected, the argument goes (Urbinati and Warren Reference Urbinati and Warren2008). In multiparty systems, collective decisions are typically made through deliberations between multiple parties in parliament. As the composition of parliament determines its collective decisions, one may posit that voters must have a strong as possible verdict on parliamentary composition. Yet, a categorical ballot vote does not allow voters to express their preferred parliamentary composition.

While we do not wish to make a conclusive statement on which institutional mechanisms should be employed to translate the views of the individuals into a collective choice, we suggest a ballot that allows voters to customize their preferred parliamentary composition: the assembly ballot (AB). The AB asks voters to create their ‘ideal parliament’ by distributing all available seats across all the participating parties they want to see represented in parliament. For instance, one might give two parties half of the seats each if one agrees with both equally, or give one party two-thirds of the seats and distribute the remaining seats over four different parties. In combination with a proportional electoral formula and a low effective threshold, the AB will produce a parliament that reflects the aggregate of all voters’ ‘ideal’ assemblies. As a result, the final parliamentary composition as well as the potential coalition governments reflect the one most voters agree on the most. The AB streamlines the process of representation as it establishes an explicit link between voter and parliament, voter and coalition government, and thus ultimately between voter and policy.

Also, while the accurate reflection of the main divisions and interests of the citizens in parliament are conceived of as the ‘proportional ideal’ (Pitkin Reference Pitkin1967), it is important to recognize that individuals might have political interests and preferences which do not neatly align with a single political party (Blais et al. Reference Blais, Guntermann and Bodet2017; van der Eijk et al. Reference van der Eijk2006). Dutch voters in particular have been found to consider an increasing number of parties for the elections (van der Meer Reference van der Meer, van der Meer, van der Kolk and Rekker2017). Indeed, as the AB allows the expression of pluralistic preferences, it may be a more suitable voting device in times of decreasing partisanship and volatility (André et al. Reference André, Depauw and Beyens2015; Dassonneville Reference Dassonneville2018). If voters do not have pluralistic political preferences or choose not to express them, however, all seats may be allocated to a single party – as in a categorical ballot. The AB does not force voters to vote differently, it merely enables them to do so. The number of ideal parliaments that can potentially be made by a voter – the number of ways a voter's electoral strength can be distributed over the options – is extremely high. For instance, an AB in a system with 150 seats to divide between 15 parties results in roughly 65 quintillion unique possible votes or seat allocations.Footnote ²

We expect voters to distribute their electoral strength around their own ideological stance – performing an ‘ideological balancing act’. If there is no perfect match between a voter's own position and a party, the voter may balance out the political positions she thinks the parties have by attributing certain seat shares to certain parties to match her own political position to the highest possible degree. Our expectation is bolstered by considerations regarding strategic and expressive voting. Strategic voting generally occurs when the voter anticipates the logic of seat allocation. As André Blais et al. (Reference Blais2012) argue, strategic voting is less likely when a vote will not be ‘wasted’. As the AB aggregates all the votes to an assembly composition there is virtually no post-electoral distortion (‘waste’) of vote shares to the seat shares. Due to such low incentives for strategic voting, voters are more geared towards ‘expressive voting’. We posit the following:

Ideological congruence between a voter and the political representatives she chooses is often measured on the general left–right dimension (Boonen et al. Reference Boonen, Pedersen and Hooghe2017; Dahlberg and Holmberg Reference Dahlberg and Holmberg2014; Lefkofridi et al. Reference Lefkofridi, Giger and Gallego2014). We expect the assembly ballot to affect congruence on the economic dimension as well as on the cultural dimension – a dimension often disregarded in congruence studies (but see Laver and Sergenti Reference Laver and Sergenti2012). In recent years, the increasing importance of this cultural dimension in party politics has been widely documented in the literature (Hooghe and Marks Reference Hooghe and Marks2009; Kriesi et al. Reference Kriesi and Kriesi2008). Both the electoral success of parties mobilizing on cultural issues and the fact that mainstream parties often react programmatically to such challengers by shifting their positions on cultural issues (Meguid Reference Meguid2005) strongly suggest that mainstream parties cannot satisfy voters’ political demand for less centrist ideological positions. Using the AB, then, voters will also be able to allocate votes to parties which adopt clearer positions on the cultural issue.

If voters indeed perform the abovementioned balancing act, both moderate left- and right-leaning voters are expected to attribute a share of seats to these left- or right-wing parties but also to centrist parties. So-called ‘centrist voters’, on the other hand, already attribute a considerable number of seats to the middle parties and will presumably be less inclined to attribute seats to non-centrist parties. As such, a more centripetal assembly composition may be expected due to the increased seat share for middle parties that comes at the cost of the non-centrist parties’ seat shares – and thereby avoiding strong parliamentary polarization (Dalton Reference Dalton2008).

Data and method

Operationalization: voter–vote congruence

Voter–vote congruence is calculated as the absolute difference between a respondent's self-placement and her vote choice. Ideological self-placement is measured by asking respondents to place themselves on an 11-point scale (1–11) for both the socioeconomic dimension and the cultural dimension.Footnote ⁵ Vote choice is either the placement of the party voted for (Boonen et al. Reference Boonen, Pedersen and Hooghe2017; Lefkofridi et al. Reference Lefkofridi, Giger and Gallego2014) or the placement of the weighted average of the multiple parties voted for within the AB format. Party placement is based on placement by academic experts, based on evidence from party platforms and other authoritative sources of party positions on issues on an 11-point scale (0–10) (for the method, see Garzia and Marschall Reference Garzia and Marschall2012; Krouwel and Elfrinkhof Reference Krouwel and Elfrinkhof2014). While political parties were also given the opportunity to provide a self-placement on all the issues constituting the two ideological dimensions, positions are only accepted when they can be corroborated by text snippets from formal documentation from election manifestos, websites, campaign material or speeches and media appearances by party leaders that justify that position (Krouwel et al. Reference Krouwel, Vitiello and Wall2012; Trechsel and Mair Reference Trechsel and Mair2011). Parties’ ideological positions are depicted in Table A1 of the online Appendix. Placements were assessed for parties that already had seats or consistently polled above two seats. Parties not meeting this threshold were excluded from the analysis.

Any vote choice is translated as a position on both issue dimensions indicated with the integral A _j in Equation 1 (A stands for Assembly). The portion of a vote (P) given to party i by voter j is indicated with P _ij. For respondents voting with a regular ballot the portion P of the vote was 1 for one party and 0 for the others. However, if a respondent voted with an AB, the score of her A _j on both dimensions was the sum of the portion P a particular party (i) had in this voter's (j) ideal parliament (anywhere between 0 and 1) multiplied by the party's score S _i.

(Equation 1)$$A_j = \mathop \sum \limits_{i = 1}^n P_{ij}S_i$$

To calculate voter–vote congruence, the absolute distance between the voter's A _j and her self-placement is calculated. The self-placement score S of respondent j is indicated with the integral S _j in Equation 2. To ease interpretation, we multiply by −1. Hence, if the distance between respondent j’s vote score and self-placement goes down, her congruence score goes up (see Equation 2).

(Equation 2)$$C_j = \; - min\vert {A_j - \; S_j} \vert $$

The maximum (ideal) score on the congruence scale is 0. The minimum (least-ideal) score is around −9. This is as much as a respondent can vote ‘wrongly’, for example by attributing herself a score of 10 on the left–right scale but voting (entirely) for the left-wing Socialistische Partij (Socialist Party, SP), which has a score of 0.4.

We calculate congruence scores for both the economic and cultural dimensions (see Germann et al. Reference Germann2015; Krouwel Reference Krouwel2012; Otjes and Louwerse Reference Otjes and Louwerse2014). A two-dimensional space is better capable of capturing issue competition between parties in European multiparty system than the Downsian model with a single left–right axis (Downs Reference Downs1957). While the economic left–right dimension is still very relevant, this dimension is in many contexts cross-cut by a cultural dimension. Also called the new politics dimension, this cultural dimension pertains to attitudes towards morality, immigration and national identity (Hooghe and Marks Reference Hooghe and Marks2018; Hooghe et al. Reference Hooghe, Marks and Wilson2002). The descriptive statistics of all variables can be found in Table A2 in the online Appendix.

Findings

Before we can assess the effect of the AB on voter–vote congruence and, subsequently, on parliamentary composition, it is important to establish the extent to which respondents actually used the AB to split up their votes. Figure 1 depicts the seat proportion a respondent allocated to the largest party when using the AB.Footnote ⁷ On average, voters gave the largest party a proportion of 0.33 (33%) of the seats, indicating that the remaining 67% were distributed over at least two other parties. A remarkable 89.6% of the respondents ‘voting’ with the AB gave no single party a majority of the seats. Most AB respondents elected between 4 and 10 parties (see Figure A1 in the online Appendix). This suggests that voters recognize the added value of a more expressive ballot.

Figure 1: Histogram of the Seat Proportion Voters Allocated to Their Largest Party in the AB

The assembly ballot's effect on ideological congruence

Now we turn to the question of whether and how the AB affects voter–vote congruence vis-à-vis the closed-list ballot. Figure 2 shows the results of the survey experiment assessing the effect of ballot type on ideological congruence. Specifically, Figure 2 depicts the predictive margins of ballot type of ideological congruence based on a simple bivariate OLS regression analysis for the economic dimension (left panel) and the cultural dimension (right panel). The values on the y-axis denote the predicted congruence score. The estimates are based on the models in Table A3 in the online Appendix. The results show that, on average, the AB improves respondents’ ideological congruence for both dimensions, as our hypothesis posited, and that these effects are statistically significant. While ideological congruence is consistently higher on the economic dimension for both ballot types, the average effect of the AB is much more pronounced for the cultural dimension. Given that the congruence variable ranges from approximately −9 to 0, the results point to a substantive improvement in congruence for the AB.

Figure 2: Predictive Margins Plot of Ballot Type on Ideological Congruence per Ideological Dimension

Yet, are all respondents equally likely to improve their congruence? The AB is expected to improve voter–vote congruence particularly for voters for whom political supply is lacking. If a voter places herself at 5 and there are two parties with scores of 3 and 7 respectively, the AB would have much added value as a voter can give both parties half the seats to get a score of 5. For a voter whose preferences perfectly align with one party, attributing seats across multiple parties logically worsens the congruence score. Therefore, we further explore whether the effect of ballot type is moderated by a voter's distance to the closest party. Moreover, ideologically extreme voters have less chance of improving their congruence score with the AB as the lack of political supply makes them less able to balance their vote. Therefore we also explore the moderating effect of self-placement on the economic and cultural dimensions on the relationship between ballot type and congruence.Footnote ⁸

First, we measure the interaction effect between the ballot type and a respondent's distance to the closest party (see Table A5 in the online Appendix). We include a quadratic term of distance to the closest party, as the Ramsey Regression Equation Specification Error Test suggested that the relationship between a respondent's distance to the closest party and ideological self-placement is not linear for both dimensions. Plotting the predictive margins of this interaction, Figure 3 shows that AB respondents almost always obtain a higher congruence score than closed-list counterparts with similar distance to the most closely located party on both the economic (left panel) and cultural dimension (right panel). Only if a voter has a ‘perfect match’ on the economic dimension is the difference between AB and closed-list voting not statistically significant. Particularly for the cultural dimension, the difference between ballot types becomes more substantial the further a respondent is ideologically removed from the most closely located party. In short, voter–vote congruence is higher for AB respondents compared with closed-list ballot respondents when distance between their own ideological position and the closest located party is not 0.

Figure 3: Predictive Margins Plot of Ballot Type on Ideological Congruence by the Distance to Closest Party per Dimension

Second, how does the ideological self-placement of respondents affect the effect of ballot type on ideological congruence? Figure 4 shows a predictive margins plot based on the interaction between ballot type and ideological self-placement for both dimensions. The plots are based on the models in Table A6 in the online Appendix. A quadratic term of self-placement was included as the relationship with the dependent variables appeared to be non-linear. The figure shows that the positive effect of the AB is limited to centrist voters. On both the economic and cultural dimensions, centrist respondents (4–8) obtain higher congruence scores when they vote with an AB, whereas respondents with extreme, non-centrist positions (1–3 and 10–11) obtain higher congruence scores when voting with the regular closed-list ballot. This is unsurprising. As centrist respondents have parties on both sides, they are better able to balance their vote to obtain a higher congruence score. Non-centrist voters are best represented by parties with similarly extreme positions. If these respondents do choose to attribute seats to other parties with the AB, they select parties that are logically more distant than the parties they would opt for under the closed-list system.

Figure 4: Predictive Margins Plot of Ballot Type on Ideological Congruence by Respondents’ Self-Placement per Dimension

The AB's effect on parliamentary composition

We now turn to the question of the effects of the AB for parliamentary composition and polarization within parliament. We have established that the AB can substantially improve ideological congruence between voters and their selected representatives. In particular, congruence scores for centrist respondents are improved. Furthermore, we found that extremist voters obtained worse congruence scores, which implies a more centrist vote choice. Both of these mechanisms should contribute to a more centrist parliamentary composition. In order to assess descriptively the consequences of the AB for the composition of the parliament, Figure 5 presents the counterfactual electoral results produced by respondents voting with a closed-list ballot (left graph) and with the assembly ballot (right graph).

Figure 5: Bar Graph of Aggregate Results from the Closed-List Vote and the AB Vote

Overall, the parties indeed converge in terms of their vote shares. The average party's size remains similar under both systems (7.4–7.5% of the vote share) but the standard deviation in percentage of the vote for the 13 parties that make the electoral threshold decreases from 6 percentage points to 5.6 percentage points. The vote shares thus appear to be distributed more evenly across all parties. The seat shares of parties with regular governing experience (Christen-Democratisch Appèl (Christian Democratic Appeal, CDA), Partij van de Arbeid (Labour Party, PvdA) and Volkspartij voor Vrijheid en Democratie (People's Party for Freedom and Democracy, VVD)) in particular are closer to one another in the AB system. But, each of these parties secure higher seat shares than under the closed-list ballot. Moreover, the figure shows that the vote share for GroenLinks (GreenLeft) – a left-wing and culturally progressive party without governing experience – decreases quite substantively under the AB. Under the AB, voters who would otherwise have fully supported GroenLinks appear to attribute a certain number of seats to parties that are in the same left-wing ‘choice-set’ (van der Eijk et al. Reference van der Eijk2006), such as the PvdA and SP – two parties that indeed grow under the AB.

The mean position of AB votes on the left–right dimension is 4.37 on a 0–10 scale with a standard deviation of 1.33.Footnote ⁹ The mean of closed-list votes’ left–right position is 4.13 (SD = 2.36). On the cultural dimension, the mean of AB votes (5.76, SD = 1.45) is also closer to the centre when compared with closed-list votes (mean = 6.09; SD = 2.60). For both dimensions, t-tests showed this difference to be statistically significant. That the means are closer to the centre and the overall Assembly Scores less dispersed suggests a centripetal effect of the AB ballot.