Cohort Effect or Age Effect?
Test a generational claim before repeating it. Six checks separating what is true of a cohort from what has always been true of people that age.
Six checks separate a genuine cohort effect from an age effect, and most circulating generational claims fail the first one — there is no measurement of people the same age in an earlier decade to compare against.
Cohort Effect or Age Effect?
Frequently asked
What is the difference between the three effects?
An age effect is true of all twelve-year-olds in every era. A period effect is something that happened to everyone alive at one moment. A cohort effect is specific to people born in a particular window. Only the third is a generational finding.
Does passing all six make a claim true?
No. It makes it the kind of claim that could be true, and worth checking the source of. A well-formed claim built on a bad survey is still wrong.
Why does this matter?
Because almost every "this generation is different" headline is an age effect with a label on it, and repeating those is how generational writing lost its credibility.
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