Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at statalist.org.
| From | Brent Gibbons <brent.gibbons@gmail.com> |
| To | statalist@hsphsun2.harvard.edu |
| Subject | st: Plotting Residuals vs Fitted Values using GLM |
| Date | Tue, 23 Oct 2012 17:57:21 -0400 |
Hello, I am working with a model that has a Dependent Variable of Total Health Costs. Other than using the log transformation, the best fit is using GLM, family(negative binomial) link(log). But I'm worried about heteroscedasticity and have been trying the rvfplot2 command. The documentation recommends the sqrt(abs(resid)) as the rscale to look at heteroscedasticity. My question is whether or not I need to use a transformation scale for the fitted values, an fscale? If so, what should that transformation be? And what should I be looking for in the plot? Thanks for all suggestions, Brent Brent Gibbons UMBC 421 PubPol brent.gibbons@gmail.com * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/faqs/resources/statalist-faq/ * http://www.ats.ucla.edu/stat/stata/