help pvstata: Help files for PathView in Stata

PathView for Stata constructs parallel coordinate graphs for categorical variables. Data consisists
of multiple categorical variables, called items, for each observation. Three commmands are to plot the data:

pvdata Create a dataset to analyze with pvplot.

pvsel Select paths to be selected or hidden in the graphs.

pvplot Plot the data created by pvdata and the
paths selected by pvsel.

Overview

The commands pvdata, pvsel and pvplot are used to plot
categorical data using a modification of the method of parallel coordinates.
With categorical variables, many observations can have exactly the same combination
of values for the variables. In traditional parallel coordinates plots a single line
or path could represent hundreds or thousands of identical observations. To allow the graph
to indicate the number of observations with each combination of categorical variables
a small offset is made between observations with the same observed values. Accordingly,
identical obsevations are represented by a set of closely stacked paths so that the width
of the paths indicates the frequency of observations. pvdata prepares the data for
plotting, pvsel selects the paths to plot, and pvplot creates
the modified parallel coordinates plot. In interactive mode, the commands pvs and
pvp make it possible to quickly modify a graph and automatically
export each graph as a file.