Measures - Overview
Measure · API Affective Polarization Index affective mass vertical Measure · Behavioral Games Behavioral Measure of Intergroup Polarization affective mass horizontal Measure · Coefficients of Agreement Coefficients of Agreement ideological issue Measure · Dispersion (Weighted) Party System Dispersion ideological elite Measure · Distance (Weighted) mean distance from the most-liked party affective mass vertical Measure · Other Polarization Measurements Other Polarization Measurements ideological issue affective elite horizontal mass vertical Measure · Party Dyads Party Dyads and In-Out-Party Differences ideological affective mass vertical Measure · Party-System Compactness Party-System Compactness ideological elite Measure · Party-System Extremism Party-System Extremism ideological elite Measure · Polarization Index CSES Polarization Index ideological elite mass Measure · Range Range Between Outer-Right and -Left Parties ideological elite Measure · SD Standard Deviation ideological elite mass Measure · Social Distance Scale Closest Acceptable Relationship with Outparty Voters affective mass horizontal Measure · Spread (Weighted) Spread of like-dislike scores affective mass vertical Measure · trait-based Trait-Based Affective Polarization affective mass horizontal Measure · Variance Weighted Variance ideological elite

Polarization measure · trait-based

Trait-Based Affective Polarization

Description

Different papers, i.e. Druckman and Levendusky (2019) or Zumbrunn (2025) use respondents’ evaluations of social or political groups along a range of positive and negative characteristics. Participants are asked to assess how strongly specific traits such as honesty, selfishness, open-mindedness, or arrogance apply to members of different groups, typically including both the in- and outgroup.

Polarization is calculated as the difference between positive and negative trait attributions across groups Iyengar et al. (2012). This approach captures polarization as a systematic tendency to attribute more favorable characteristics to the in-group while assigning more unfavorable characteristics to the out-group.

Conceptually, this measure is rooted in theories of social identity and intergroup bias, which suggest that individuals maintain a positive self-concept by positively distinguishing their own group from others. As such, polarization manifests not only in differences in opinions or preferences but also in how groups are perceived and characterized.

By focusing on trait attributions rather than explicit attitudes toward policies or behaviors, this measure captures the affective and cognitive dimensions of polarization, reflecting deeper evaluative biases that structure intergroup perceptions. Higher levels of trait-based polarization therefore indicate stronger ingroup favoritism and outgroup derogation.

Operationalization

Affective Polarization can be operationalized as the difference of the average rating for the respective traits between the ingroup and the outgroup:

$AP_{trait}=\bar{x}{ingroup}-\bar{x}{outgroup}$

with $\bar{x}$ being the average trait rating for the respective group.

Use cases

Publications that use this measure:

TitleAuthors
What Do We Measure When We Measure Affective Polarization?
  • Druckman and Levendusky (2019)
Divided by the Vote
  • Hobolt et al. (2020)
Affect, Not Ideology
  • Iyengar et al. (2012)
Populist attitudes, cleavage identification, and polarization in Austria and Germany
  • Jungkunz and Helbling (2025)
We Need to Talk
  • Levendusky and Stecula (2023)
The unifying magic of the unwaved flag
  • Nordbrandt, Gustavsson und Breidahl (2026)
An unrequited conflict
  • Zumbrunn (2025)
TitleAuthors