Russell J. Dalton

1. The quantity and the quality of party systems. Party system polarization, its measurement, and its consequences. Comparative Politics, 2012-2013 Russell J. Dalton Anna Zaremba

2. ‘Quality should count more than quantity’.

3. Quality vs. quantity • Many studies concentrate on the number of parties • Consequences attributed to the number of parties are often linked to the degree of polarization of party system. • The polarization of the party system can be independent of number of parties

4. Polarization • Two approaches: Anthony Downs: spatial model in which political parties and voters are aligned along a Left and Right continuum. Two-party system converges toward the center, multiparty system spreads along Left-Right dimension.

5. Polarization (2) • Giovanni Sartori: there are centripetal and centrifugal forces that influence the locations along Left-Right dimension. In multiparty systems these forces may produce polarized pluralism. • German Weimar system, postwar Italian and French system.

6. Measuring party system characteristics • Party fractionalization index (the Herfindahl index) • Measure of the effective number of parties (Laasko-Taagepera index)

7. Measuring polarization • A concept that is difficult to be measured • Estimated from indirect indicators, e.g. number of parties in an electoral system, the size of extremist parties, the vote share for the governing parties, party manifestos • Dalton uses the perception of the electorate in the nation, the database of Comparative Studies of Electoral System.

8. 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?

9. Citizens Placement of Parties on the Left-Right Scale

10. Polarization index • It takes a value of 0 when all parties occupy the same position on the Left-Right scale and 10 when the parties are split between two extremes.

12. More parties do not necessarily cause higher level of polarization (r=.067) • District magnitude has a higher correlation with polarization (r=.338) • Fractionalization is higher in new electoral systems but the relation is insignificant (r=.087), polarization is higher in established party system. • Downs: polarization reflects the dispersion of citizens along the scale. The empirical results do not confirm the hypothesis (r=.144) • Party polarization reflects rather the internal dynamics of electoral competition in a nation than institutional or social characteristics.

13. The polarization of voter preferences • Hypothesis: diverse party choice should strengthen polarization of voters. If parties are distinctive in their issue positions, then issues can have greater weight, all else being equal. • Test: calculation of the relationship between social class and party support, examination of the variation in the correlation of the Left-Right self-placement with party choice

14. Is the fractionalization correlated with strength of class voting? • Is the polarization correlated with strength of voting? • What’s the impact of the Left-Right self-placement on vote preferences taking into account polarization and fractionalization?

15. The Impact of Left–Right Attitudes on Vote Preferences as a Function of Party Polarization

16. The Impact of Left–Right Attitudes on Vote Preferences as a Function of Party Fractionalization

17. Results • Observablecorrelation betweenfractionalization and the strength of class voting (.32). • Even stronger relation in case of polarization (.47) • Very strong relationship between the party polarization and the correlation between Left-Right attitudes and party choice (r=.633) • Fractionalization is unrelated to the strength of the Left-Right relationship (r= -.020)

18. Explanation • With more choice, voters can better translate their Left-Right orientation into a party preferences • What matters is not the number of parties but their ideological diversity. • The correlation between Left–Right attitudes and party preferences can be stronger in a system with fewer parties but more polarization than in a system with many parties but less polarization.

19. The party system and voting turnout • Hypothesis: Dispersion of parties on the Left-Right scale has an influence on voting turnout • Three regression models including different predictors • Polarization • Fractionalization • Both polarization and fractionalization All the models contain also two institutional factors: compulsory voting and whether there were simultaneous executive and parliamentary elections.

20. The Predictors of Voting Turnout (N = 29)

21. Results • The polarization of party system has a positive effect on the voter turnout (β=.289 and β=.264). • Fractionalization has approximately half the impact of the polarization variable. • Compulsory voting in all three models has an important impact on the turnout. • The nature of the choices available to the voters is strongly related to the level of turnout.

22. Conclusions • Counting the number of parties is often a surrogate for a richer characteristic of a party system that is more difficult to measure—party system polarization. • Polarization and fractionalization can vary almost independently of one another. • The polarization is related to stronger correlation betweenLeft-Right attitudes and party choice. • Voting turnout seems to be more strongly correlated with polarization than with fractionalization.