Stata’s main data model treats observations in rows and variables in columns quite differently, but rowwise problems also arise that require working against the grain. This column shows how to exploit existing functions and egen functions when they exist and apply to such problems. It offers...

Distinct observations are those different with respect to one or more variables, considered either individually or jointly. Distinctness is thus a key aspect of the similarity or difference of observations. It is sometimes confounded with uniqueness. Counting the number of distinct...

Many problems in data management center on relating values to values in other observations, either within a dataset as a whole or within groups such as panels. This column reviews some basic Stata techniques helpful for such tasks, including the use of subscripts, summarize, by:, sum(), cond(),...

Box plots have been a standard statistical graph since John W. Tukey and his colleagues and students publicized them energetically in the 1970s. In Stata, graph box and graph hbox are commands available to draw box plots, but sometimes neither is sufficiently flexible for drawing some variations...