You can use the matrix computations in SAS/IML to 'manually' compute the coordinates of the markers and vectors.You can then use PROC SGPLOT to create a modern version of Friendly's biplot. If you have a license for SAS/GRAPH software (and SAS/IML software), you can use Friendly's %BIPLOT macro and use the OUT= option in the macro to save the coordinates of the markers and vectors.You can use PROC PRINQUAL in SAS/STAT software to create the COV biplot.There are four ways to create biplots in SAS by using ODS statistical graphics: The %BIPLOT macro is very powerful and flexible it is discussed later in this article. You can obtain biplots that use the traditional SAS/GRAPH system by using the %BIPLOT macro by Michael Friendly. In particular, the goal is to create the biplots by using modern ODS statistical graphics. This article shows how to create biplots in SAS. There are four common scalings (GH, COV, JK, and SYM), which are discussed in the previous article.
The observations and/or vectors are not usually on the same scale, so they need to be rescaled so that they fit on the same plot.
The observations are plotted as markers the variables are plotted as vectors.
The biplot projects observations and variables onto the span of the first two principal components. A previous article discusses how to interpret biplots for continuous variables. Biplots are two-dimensional plots that help to visualize relationships in high dimensional data.
