Final answer:
Political Science researchers measure party identification primarily through surveys and self-identification, which helps to predict voting behavior. Party identification is a key heuristic for voters, significantly influencing their decisions, especially when detailed candidate information is scarce.
Step-by-step explanation:
In the field of Political Science, researchers typically measure party identification a) Through surveys and self-identification. This method allows individuals to express their political affiliations without the need for formal party membership. Party identification plays a crucial heuristic role as voters often rely on party alignment to make decisions during elections, especially when there is limited information about the candidates.
Gallup, a polling agency, has extensively collected data on voter preferences, finding that a significant portion of American adults identify themselves as either 'Republican' or 'Democrat.' Moreover, even those who consider themselves independents tend to lean towards one party, influencing their voting behavior akin to declared party supporters.
Party identification is mainly an informal yet decisive factor that guides voters who may be less informed about a particular issue or candidate, especially in the lead-up to elections. Political scientists and analysts use surveys among other tools to predict electoral behaviors based on this self-identification data, demographic characteristics, and historical voting patterns.