Partisan Identity Scale
Partisan Identity and Party Attachment Scale (PAS) · Also known as: PAS, Party Identification, Partisan Strength
The Partisan Identity Scale measures strength and direction of psychological attachment to a political party, encompassing both party preference and emotional party identification. Foundational since Campbell et al.'s American Voter (1960), the measure distinguishes party affiliation (which party one is registered with) from party identification (psychological identity with a party as a social group). Partisan identity is among the strongest predictors of voting behavior, political attitudes, and interpretation of political information, functioning as a 'perceptual filter' through which voters process news.
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When to use it
Use Partisan Identity Scale in election forecasting models, studies of political behavior and voting stability, research on partisan polarization and affective polarization, analyses of partisan bias in information processing and media consumption, studies of political engagement and activism, and comparative research examining differences in partisan identification strength across democracies. Appropriate for adult voting populations and politically aware youth (16+). Essential in any voting behavior model; serves as primary predictor. Useful in longitudinal tracking of partisan realignment and dealignment.
Strengths & limitations
- Simplicity and stability: single-item or two-item question, remarkably stable over decades, test-retest r > 0.90.
- Predictive power: strongest single predictor of voting behavior (r = 0.80+); superior to ideology alone.
- Social group meaning: captures identity component not captured by ideology or issue positions; explains why partisans interpret identical event differently.
- Cross-national validity: party identification concept generalizes across diverse party systems and democracies, though comparative measurement remains challenging.
- Endogeneity: difficult to determine causation. Does party identification drive policy preferences (identity-driven) or do policy preferences drive party choice (rational choice)? Likely bidirectional.
- Partisan sorting: in recent decades, partisan identity increasingly correlates with ideology, identity, and cultural values, making isolation of party effect difficult.
- System-specific meaning: party identification means different things in two-party systems (binary choice) vs. multiparty systems (proportional representation); non-comparable across system types.
- Non-response complications: in multiparty systems, respondents often claim 'no party' not from independence but from inability to choose among multiple parties; creates measurement ambiguity.
Frequently asked
Why is party identification so stable when people change issue preferences?
Party identification operates as social identity (like ethnic identity) rather than pure policy preference. People update positions to align with party rather than updating party to align with positions. This is rational: switching parties requires abandoning social group, explaining why issue change rarely causes partisan switching. However, major political realignments (e.g., 1930s New Deal realignment, 1960s civil rights realignment) do shift partisan identification when party brands fundamentally change.
Are independents truly independent or just non-partisan weak partisans?
Research distinguishes 'pure independents' (no party lean) from 'partisan leaners' (claim independent but lean one direction). Partisan leaners behave nearly identical to weak partisans in voting (r > 0.85). Pure independents are rarer (10-15%) and genuinely more persuadable. Recent surveys show leaners increasing (as people claim independence while becoming more partisan), complicating interpretation of 'independent' label.
Can partisan identity change through campaigns and media?
Short-term: minimal. Campaigns may shift weak partisans' voting but rarely change identification. Long-term: yes. Sustained media messaging, party repositioning on new issues, and perceived party performance can shift identification, particularly among younger voters not yet fully socialized. Immigration and culture war realignment (2000s-2010s) shifted partisan identity: working-class voters switched from Democratic to Republican despite policy disagreement, following cultural identity (conservative social values) rather than economic interest.
Is partisan identification the same across democracies?
Conceptually similar but measurement and strength vary. Two-party systems (USA, UK) show clear partisan divide; multiparty systems (Germany, Netherlands) require respondents to choose 'closest party,' making strength less meaningful. Nordic countries show weaker partisan identification; voters more willing to switch parties between elections. Proportional representation systems show lower partisanship than winner-take-all systems. Comparable measurement requires system-specific adaptation.
Sources
- Campbell, A., Converse, P. E., Miller, W. E., & Stokes, D. E. (1960). The American voter. New York: John Wiley & Sons. link ↗
- Carsey, T. M., & Layman, G. C. (2006). Changing sides or changing minds? Party identification and policy preferences in the American electorate. American Journal of Political Science, 50(2), 464-477. DOI: 10.1111/j.1540-5907.2006.00196.x ↗
- Greene, S. (2004). Social identity and the psychological attachment to parties. In D. M. Sears, L. Huddy, & R. Jervis (Eds.), Oxford handbook of political psychology. Oxford: Oxford University Press. link ↗
How to cite this page
ScholarGate. (2026, June 3). Partisan Identity and Party Attachment Scale (PAS). ScholarGate. https://scholargate.app/en/political-psychology/partisanship-scale
Which method?
Set this method beside its closest kin and read them side by side — the library lays the books on the table; the choice is yours.
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