John Fox wrote: > Dear Frank, > > The object is to focus on a high-order term of the model, holding other > terms "constant" at typical values; in the case of a factor, a "typical > value" is ambiguous, so an average is taken over the levels of the factor. > If the factor is, e.g., gender, one could produce an estimate of the average > fitted value for a population composed equally of men and women, or of a > population composed of men and women in proportion to their distribution in > the data. Otherwise, one would have to produce separate sets of fitted > values for men and women, with the number of such sets increasing as the > number of levels of the factors held constant increase. On the scale of the > linear predictor, these sets would differ only by constants. > > Regards, > John
Makes sense. I just set other factors to the mode, and if it is important to see estimates for other categories, I give estimates for each factor level. If I want to uncondition on a variable (not often) I take the proper weighted average of predicted values. Cheers Frank > > -------------------------------- > John Fox > Department of Sociology > McMaster University > Hamilton, Ontario > Canada L8S 4M4 > 905-525-9140x23604 > http://socserv.mcmaster.ca/jfox > -------------------------------- > >> -----Original Message----- >> From: Frank E Harrell Jr [mailto:[EMAIL PROTECTED] >> Sent: Thursday, March 22, 2007 8:41 AM >> To: John Fox >> Cc: 'Prof Brian Ripley'; 'r-help'; 'Chuck Cleland'; 'Liaw, Andy' >> Subject: Re: [R] how to get "lsmeans"? >> >> John Fox wrote: >>> Dear Brian et al., >>> >>> My apologies for chiming in late: It's been a busy day. >>> >>> First some general comments on "least-squares means" and >> "effect displays." >> ... much good stuff deleted ... >> >> John - the one thing I didn't get from your post is a >> motivation to do all that as opposed to easy-to-explain >> predicted values. I would appreciate your thoughts. >> >> Thanks >> Frank >> >> -- >> Frank E Harrell Jr Professor and Chair School of Medicine >> Department of Biostatistics >> Vanderbilt University > > -- Frank E Harrell Jr Professor and Chair School of Medicine Department of Biostatistics Vanderbilt University ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.