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...djr2==max(var.selection$adjr2),] 1 2 3 4 TRUE TRUE TRUE FALSE Actually, I use the definition of R-square in which the model is without a intercept term. Is what I am doing is correct? Thanks for any suggestion or correction. -- Junjie Li, klijunjie@gmail.com Undergranduate in DEP of Tsinghua University, [[alternative HTML version deleted]]

...culated by lm(y~xx-1) > lm=lm(y~xx-1) > summary(lm)$r.squared [1] 0.9365253 > ### r2 calculated by me > y.hat=xx%*%lm$coefficients > (r.square=sum((y.hat-mean(y))^2)/sum((y-mean(y))^2)) [1] 0.9231062 Thanks a lot for any cue:) -- Junjie Li, klijunjie@gmail.com Undergranduate in DEP of Tsinghua University, [[alternative HTML version deleted]]

...you will find the residues are all derived from a model with only one predictor, but the coefficient of that only one predictor can be calculated from a model with more than one predictors which you've set in the formula term in cv.lm(DAAG), -- Junjie Li, klijunjie@gmail.com Undergranduate in DEP of Tsinghua University, [[alternative HTML version deleted]]

...hough it seems plausible, this function doesn't work > n=1000 > x=rnorm(n)+10 > y=rnorm(n)-10 > permutation.test.bias(x,y) [1] 0 I think there should be other test methods for this problem. Thanks for any suggestion/solution. -- Junjie Li, klijunjie@gmail.com Undergranduate in DEP of Tsinghua University, [[alternative HTML version deleted]]

...l mss(mean squared error). I checked the code of function cv.lm(DAAG), then found the residues were all derived from a model with only one predictor. Is this a bug? Or is it because of my misunderstanding of somthing about cv.lm(DAAG)? Li Junjie -- Junjie Li, klijunjie@gmail.com Undergranduate in DEP of Tsinghua University, [[alternative HTML version deleted]]

...=y,x=x[,comb[[i]]]) glm=glm(y~.-1,data=data) pe1[i]=cv.glm(data,glm)$delta[1] } var=rep(0,n.var) if(min(pe)<min(pe1)){ int=1 var[comb[[which(pe==min(pe))]]]=1 }else{ int=0 var[comb[[which(pe1==min(pe1))]]]=1 } c(int,var) } -- Junjie Li, klijunjie@gmail.com Undergranduate in DEP of Tsinghua University, [[alternative HTML version deleted]]