search for: outome

Hello, I have spent considerable time trying to figure out that which I am about to describe. This included searching Help, consulting my various R books, and trail and (always) error. I have been assuming I would need to use a loop (looping over columns) but perhaps and apply function would do the trick. I have unsuccessfully tried both. A scaled down version of my situation is as follows:

...oefficients for the predictor in separate models fxb <- function(x) {lm(Outcome.1~Pred,da=x)$coef}; by(new,new$sex,fxb) #yields the coefficient for Outcome.1 for each sex ## I'd like to be able to combine 'sapply' and 'by' to be able to get the regression coefficients for Outome.1 and Outcome.2 by each sex, rather than running fxb a second time predicting 'Outcome.2' or by subsetting the data - by sex - before I run the function, but the following doesn't work - by(new,new$sex,FUN=function(x)sapply(x[,1:2],fxa,new)) 'Error in model.frame.default(formula =...

...oefficients for the predictor in separate models fxb <- function(x) {lm(Outcome.1~Pred,da=x)$coef}; by(new,new$sex,fxb) #yields the coefficient for Outcome.1 for each sex ## I'd like to be able to combine 'sapply' and 'by' to be able to get the regression coefficients for Outome.1 and Outcome.2 by each sex, rather than running fxb a second time predicting 'Outcome.2' or by subsetting the data - by sex - before I run the function, but the following doesn't work - by(new,new$sex,FUN=function(x)sapply(x[,1:2],fxa,new)) 'Error in model.frame.default(formula =...