search for: seroc

Please help. I found the code in the archive. The author of this script says: "The first function (seROC) calculate the standard error of ROC curve, the second function (cROC) compare ROC curves." Can some one explain to me what are the na, nn and r parameters which are used as the input to the following two functions? Thanks much in advance. > From: Bernardo Rangel Tura > Date: Thu 16...

...gnose lameness in dogs. I have several ROC curves from the same dataset. I plotted the ROC curves and calculated AUC with the ROCR package. I would like to compare the AUC. I used the following program I found on R-help archives : From: Bernardo Rangel Tura Date: Thu 16 Dec 2004 - 07:30:37 EST seROC<-function(AUC,na,nn){ a<-AUC q1<-a/(2-a) q2<-(2*a^2)/(1+a) se<-sqrt((a*(1-a)+(na-1)*(q1-a^2)+(nn-1)*(q2-a^2))/(nn*na)) se } cROC<-function(AUC1,na1,nn1,AUC2,na2,nn2,r){ se1<-seROC(AUC1,na1,nn1) se2<-seROC(AUC2,na2,nn2) sed<-sqrt(se1^2+se2^2-2*r*se1*se2) zad<-(AUC1-AU...

...gnose lameness in dogs. I have several ROC curves from the same dataset. I plotted the ROC curves and calculated AUC with the ROCR package. I would like to compare the AUC. I used the following program I found on R-help archives : From: Bernardo Rangel Tura Date: Thu 16 Dec 2004 - 07:30:37 EST seROC<-function(AUC,na,nn){ a<-AUC q1<-a/(2-a) q2<-(2*a^2)/(1+a) se<-sqrt((a*(1-a)+(na-1)*(q1-a^2)+(nn-1)*(q2-a^2))/(nn*na)) se } cROC<-function(AUC1,na1,nn1,AUC2,na2,nn2,r){ se1<-seROC(AUC1,na1,nn1) se2<-seROC(AUC2,na2,nn2) sed<-sqrt(se1^2+se2^2-2*r*se1*se2) zad<-(AUC1-AU...

...se x axis only goes to 0.1 not 1) I came to know about the Mcneil Hanley test from Bernardo Rangel Tura and I referred to the original paper for the calculation of "r" which is an argument of the function cROC. I can only find the value of "r" for the whole AUC's . > seROC<-function(AUC,na,nn){ > a<-AUC > q1<-a/(2-a) > q2<-(2*a^2)/(1+a) > se<-sqrt((a*(1-a)+(na-1)*(q1-a^2)+(nn-1)*(q2-a^2))/(nn*na)) > se > } > > cROC<-function(AUC1,na1,nn1,AUC2,na2,nn2,r){ > se1<-seROC(AUC1,na1,nn1) > se2<-seROC(AUC2,na2,nn2) > &...

Dear R-helper, I would like to compare the AUC of two logistic regression models (same population). Is it possible with R ? Thank you Roman Rouzier [[alternative HTML version deleted]]