Obtaining the adjusted r-square given the regression coefficients

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Obtaining the adjusted r-square given the regression coefficients

Alexandra R. M. de Almeida
Hi people,
 I want to obtain the adjusted r-square given a set of coefficients (without the intercept), and I don't know if there is a function that does it. Exist????????????????
 I know that if you make a linear regression, you enter the dataset and have in "summary" the adjusted r-square. But this is calculated using the coefficients that R obtained,and I want other coefficients that i calculated separately and differently (without the intercept term too).
 I have made a function based in the equations of the book "Linear Regression Analisys" (Wiley Series in probability and mathematical statistics), but it doesn't return values between 0 and 1. What is wrong????
 The functions is given by:
                       
adjustedR2<-function(Y,X,saM) {    if(is.matrix(Y)==F) (Y<-as.matrix(Y))    if(is.matrix(X)==F) (X<-as.matrix(X))    if(is.matrix(saM)==F) (saM<-as.matrix(saM))    RX<-rent.matrix(X,1)$Rentabilidade.tipo    RY<-rent.matrix(Y,1)$Rentabilidade.tipo    r2m<-matrix(0,nrow=ncol(Y),ncol=1)    RSS<-matrix(0,ncol=ncol(Y),nrow=1)    SYY<-matrix(0,ncol=ncol(Y),nrow=1)    for (i in 1:ncol(RY))    {       RSS[,i]<-(t(RY[,i])%*%RY[,i])-(saM[i,]%*%(t(RX)%*%RX)%*%t(saM)[,i])       SYY[,i]<-sum((RY[,i]-mean(RY[,i]))^2)       r2m[i,]<-1-(RSS[,i]/SYY[,i])*((nrow(RY))/(nrow(RY)-ncol(saM)-1))    }    dimnames(r2m)<-list(colnames(Y),c("R-square"))    return(r2m) }
 
 
 Thanks!
 Alexandra
 



  Alexandra R. Mendes de Almeida

                                                 


               
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