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 (stAK and stAL). Does R really know to turn all categorical variables in binary dummy variables? I have tried answering the question on my own and have found:
When including categorical variables in a regression, the default in R is to set the first level as the base. Is there an option to specify a different level as the base? My next/same question is what does it mean to "set the first level as the base" does this mean it turns each value into a unique binary result? ******************************** CONFIDENTIALITY NOTICE ******************************** This message (including any attachments) is intended onl...{{dropped:21}} ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.