[S] Adjusted variables plots

John Thaden (jjthaden@life.uams.edu)
Fri, 06 Mar 1998 14:30:06 -0600


I want to look for high-influence observations in my dataset. The Cook's
distance is useful, but I'm interested in looking at influentials
separately for each coefficient of a multivariate regression. I've used
adjusted-variables plots (I think they are also called partial-regression
plots) in the past to find outliers and leverage points. So for the k-th
coefficient coefficient Beta sub-k, I would plot residuals of the
regression of outcome Y on all predictors X except the k-th, versus
residuals of the regression of the k-th X on all X's except the k-th.

Before I try to write a function to speed up this type of diagnostic
analysis, I'm wondering is such a function exists? Or can predict() be
used to this end? I've found nothing in the SPlus v. 4.0 documentation.
Should I be looking in libraries contributed by others?

-----------------------------------------------------------------------
This message was distributed by s-news@wubios.wustl.edu. To unsubscribe
send e-mail to s-news-request@wubios.wustl.edu with the BODY of the
message: unsubscribe s-news