search for: tconfidence

...dence vectors" based on a new x vector by defining a new data to do predictions: x0 <- seq(0,15,1) dataci<-predict(as.lm(modellogis), newdata=data.frame(x=x0), interval = "confidence") BUt it does not work: I get the same initial confidence interval Any ideas on how to get tconfidence and prediction intervals using new X data on a previous model? Thanks Francisco ---------------------- Francisco Mora Ardila Estudiante de Doctorado Centro de Investigaciones en Ecosistemas Universidad Nacional Aut?noma de M?xico