Dear Professor Firth, David Firth said the following on 2005-06-16 17:22:
> I do not have a ready stock of other examples, but I do have my own > version of a family function for this, reproduced below. It differs > from yours (apart from being a regular family function rather than using > a modified "quasi") in the definition of deviance residuals. These > necessarily involve an arbitrary constant (see McCullagh and Nelder, > 1989, p330); in my function that arbitrariness is in the choice eps <- > 0.0005. I don't think the deviance contributions as you specified in > your code below will have the right derivative (with respect to mu) for > observations where y=0 or y=1. I'm sorry for the late reply. You're right -- my definition of the deviance residuals isn't correct. Your code, on the other hand, seems to do the right thing. Many thanks for this note and the provided `wedderburn' function. Henric ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
