search for: responsevar

...example I want to know what percentage of group 1 (which may have a value of 34456) choose response 1 and so on. Here is some code I wrote that generates a data frame like the one I have. pop <- matrix(1:100000) groupIDs <- sample(pop,500) groupVar <- sample(groupIDs,23000,replace=TRUE) responseVar <- sample(1:5,23000,replace=TRUE) example.data <- data.frame(groupVar,responseVar) Is there a fast way to calculate these percentages beyond writing loops to manually count the responses for each of the groups? Thanks, EG [[alternative HTML version deleted]]

Hey everyone, I know I've come across this somewhere, in either the blue or white books or in one of the help docs but I can't put my hand on it. What's the name of the statistical notation used in R? responseVar ~ anExplantory:anotherExplantory + thridExplantory Is this part of a coherent framework of notation that is as applicable to models which are not generalized linear models as to glms? Are there alternative systems of notation which are equally effective or even more general that any of you could...