On Variability

An important part of research methods is understanding concepts in measurement. Those include central tendency and variability. Of these, variability is more probably difficult to understand.

A couple of recent articles have highlighted the long-running longitudinal study, funded by W.T. Grant. One of those, in The Atlantic details many of the facets of his longitudinal study. Another, in the New York Times summarizes the work.

The study is remarkable because the 268 students were specially selected from the Harvard University classes of 1942, 1943, and 1944 for being among the most well-adjusted members of those classes (in other words, selected for their relative LACK of variability). Yet, over the years the life trajectories diverged incredibly. One member (John F. Kennedy) became president while another died after falling down a set of stairs, drunk.

Psychology is complex and individuals who may seem similar at one point in their lives may diverge from each other later for a wide variety of reasons. Finding those reasons is a goal of research.