Hi There,

While looking through the mailing list archive, I did not come across a simple minded example regarding the creation of dummy variables. The Gauss language provides the command "y = dummydn(x,v,p)" for creating dummy variables.
Here:


x = Nx1 vector of data to be broken up into dummy variables.
v = Kx1 vector specifying the K-1 breakpoints
p = positive integer in the range [1,K], specifying which column should be dropped in the matrix of dummy variables.
y = Nx(K-1) matrix containing the K-1 dummy variables.


My recent mailing list archive inquiry has led me to examine R's "model.matrix" but it has so many options that I'm not seeing the forest because of the trees. Is that really the easiest way? or is there something similar to the dummydn command described above?

To provide a concrete scenario, please consider the following. Using the above notation, say, I had:

x <- c(1:10)      #data to be broken up into dummy variables
v <- c(3,5,7)     #breakpoints
p =  1                #drop this column to avoid dummy variable trap

How can I get a matrix "y" that has the associated dummy variables for columns?
Thank You,
-Francisco


______________________________________________
[EMAIL PROTECTED] mailing list
https://www.stat.math.ethz.ch/mailman/listinfo/r-help

Reply via email to