THE QUANTITY AND THE QUALITY OF
PARTY SYSTEMS. PARTY SYSTEM
POLARIZATION, ITS MEASUREMENT,
AND ITS CONSEQUENCES.
Russell J. Dalton
Comparative Politics, 2012-2013
Anna Zaremba
‘Quality should count more
than quantity’.
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

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.
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.

MEASURING PARTY SYSTEM
CHARACTERISTICS


Party fractionalization index (the Herfindahl
index)
Measure of the effective number of parties
(Laasko-Taagepera index)
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.

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?
CITIZENS PLACEMENT OF PARTIES
ON THE LEFT-RIGHT SCALE
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.
 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.
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 selfplacement with party choice



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 selfplacement on vote preferences taking into
account polarization and fractionalization?
THE IMPACT OF LEFT–RIGHT ATTITUDES ON VOTE
PREFERENCES AS A FUNCTION OF PARTY
POLARIZATION
THE IMPACT OF LEFT–RIGHT ATTITUDES ON VOTE
PREFERENCES AS A FUNCTION OF PARTY
FRACTIONALIZATION
RESULTS
Observable correlation between fractionalization
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 LeftRight attitudes and party choice (r=.633)
 Fractionalization is unrelated to the strength of
the Left-Right relationship (r= -.020)

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.

THE PARTY SYSTEM AND VOTING TURNOUT


1.
2.
3.
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.
THE PREDICTORS OF VOTING TURNOUT (N = 29)
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.
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
between Left-Right attitudes and party choice.
 Voting turnout seems to be more strongly
correlated with polarization than with
fractionalization.
