ABSTRACT
The study of vital events made such consistent use of rates in the past that these rates may still appear to some people to be the most refined tools available for demographic analysis. In demography it is always of interest to relate the observed event to an event that necessarily precedes it. Events assembled for a cohort analysis are indicated in an “oblique column” in the Lexis diagram; those assembled for a period analysis are indicated in a “vertical column”. This chapter presents some general observations concerning methods of analysis of vital events. With modern statistics, observations upon real cohorts usually come from relating observations made during successive calendar years. The conditions of statistical observation lead us quite naturally to events that occur during a given interval of time in a given population group. The chapter argues that the main body of quantitative information concerning vital events is the subject of the statistics of population change.
