Cohort (statistics)

In sociology, demography and statistics are cohort groups of individuals who have in common that they had experienced a specific, long- defining event. The division into cohorts may help to define population groups. Depending on the start event can be, for example, by age or birth cohorts ( cf. generation ) to act marriage cohorts or cohorts entering the profession. In population studies only birth cohorts are referred to as " cohort ", such as the vintage 2003.

It is by definition required a similar cultural environment for a cohort. Differences that exist between different cohorts and thus can be attributed to the existence of different social and environmental influences are referred to as " cohort effects ".

In the case of the staggered cohort technique is an empirical study in which cohorts at recurring intervals on certain characteristics assayed for (eg Cognitive Development ). Also in this method, a comparison with other cohorts possible ( eg comparison of certain characteristic values ​​of the transition year cohort 1990 cohort year of 1960).

Cohort strength

The cohort strength, the number of members of a cohort, is important in regard to the question of the capacity of the generation contract. Since the cohort of contributors loses in the pension in the last decades in relation to the cohort of pensioners in strength, are increasingly competing financial problems in the financing of pensions.

Problems of cohort analysis

Since age, period and cohort effects can occur in any event at the same time, there are in each experiment an empirical assignment of an event to an effect an identification problem ( Renn, 1987).