coding for categorical variables with unequal observations
I think you need to do some background reading. R does this automatically for you, and offers many options for how it is done. (That you have asked suggests you have missed that.) The account by Bill Venables in chapter 6 of MASS (the book, see the R FAQ) is regarded as the most comprehensive available.
On Thu, 3 Apr 2008, Tanya Yatsunenko wrote:
Also, since I just started to use R, I have trouble generating and understanding some of the codes, especially choosing the correct ones. Thanks! tanya On Thu, Apr 3, 2008 at 3:54 PM, Tanya Yatsunenko <yata25 at gmail.com> wrote:
Hi, I am doing multiple regression, and have several X variables that are categorical. I read that I can use dummy or contrast codes for that, but are there any special rules when there're unequal #observations in each groups (4 females vs 7 males in a "gender" variable)? Also, can R generate these codes for me? THanks.
-- Tanya [[alternative HTML version deleted]]
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