On 2 Mar 2006, at 17:56, Prof Brian Ripley wrote: > On Thu, 2 Mar 2006, Yan Wong wrote: > >> >> Indeed, I realised this, but assumed that the problem could be >> understood even without my dataset. I'll test my data on the patched >> version when it becomes available, and re-post then.
I've just tried R-patched, and it now works as expected. Thanks for the quick fix. As you point out, the glm and lm versions differ in AIC reported, but only by an additive constant, and so the tests are not affected. Yan -------------------- > weighted.lm <- lm(trSex ~ (river+length +depth)^2-length:depth, dno2, weights=males+females) > d1.lm <- drop1(weighted.lm, test="F"); > weighted.glm <- glm(trSex ~ (river+length +depth)^2-length:depth, dno2, weights=males+females, family="gaussian") > d1.glm <- drop1(weighted.glm, test="F"); > > #differ by a constant > d1.lm$AIC - d1.glm$AIC [1] 628.1381 628.1381 628.1381 > > Anova(weighted.lm) Anova Table (Type II tests) Response: trSex Sum Sq Df F value Pr(>F) river 1.471 1 3.3775 0.06843 . length 1.002 1 2.2999 0.13187 depth 2.974 1 6.8295 0.01005 * river:length 0.075 1 0.1733 0.67790 river:depth 2.020 1 4.6397 0.03313 * Residuals 55.303 127 --- Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 > d1.lm Single term deletions Model: trSex ~ (river + length + depth)^2 - length:depth Df Sum of Sq RSS AIC F value Pr(F) <none> 55.303 -104.710 river:length 1 0.075 55.379 -106.529 0.1733 0.67790 river:depth 1 2.020 57.324 -101.938 4.6397 0.03313 * --- Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 > d1.glm Single term deletions Model: trSex ~ (river + length + depth)^2 - length:depth Df Deviance AIC F value Pr(F) <none> 55.30 -732.85 river:length 1 55.38 -734.67 0.1733 0.67790 river:depth 1 57.32 -730.08 4.6397 0.03313 * --- Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 ______________________________________________ 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