Formative experiences create cohort effects when distinctive orientations persist as the cohort ages.

Repeated cross-sections compare new samples over time; panels reinterview the same people. Both help distinguish a lasting cohort imprint from a temporary age difference.

A generation is not defined merely by current age. The cohort claim is that people exposed to distinctive conditions during a formative period retain an orientation as every cohort grows older. Repeated observations are needed because age, birth year, and historical period are mathematically linked; a single survey cannot identify which of the three produced an age gap. Consider what happens when young adults show low trust after a major scandal. If their trust remains unusually low decades later compared with other cohorts at the same age, a cohort interpretation gains support. If every cohort recovers together, a temporary period effect is more plausible.

Video lesson: Political socialization | US government and civics | Khan Academy