[R] categorical variables

I am doing a logistic regression, and by accident I included a field which has the 2digit abbreviation for all 50 states labeled "st". I was surprised to see that the glm did not come up with an error message but instead appears to have automatically broken down this field into individual fields (

[R] "rpart" or "tree" function issue

I am trying to create a classification tree using either tree or rpart functions but when it comes to plotting the results the formatting I get is different than what I see in all the tutorials (like http://www.youtube.com/watch?v=9XNhqO1bu0A or http://www.youtube.com/watch?v=m3mLNpeke0I&feature=re

[R] rpart/tree issue

I am trying to create a classification tree using either tree or rpart but when it comes to plotting the results the formatting I get is different than what I see in all the tutorials. What I would like to see is the XX/XX format but all I get is a weird decimal value. I was also wondering how yo