Data Structures for Longitudinal Analysis
In this chapter we will cover longitudinal data marts. In longitudinal data marts we have observations over time. This means that time or a sequential ordering is included in these data marts by a time or sequence variable.
Longitudinal data marts do not have an analysis subject such as in multiple-rows-per-subject data marts. They can represent one or more variables measured on several points in time, as we see in the following examples.
Or longitudinal data marts ...