computationally singular error with mice()
Hi Fei, I wouldn't worry to much about categorical variables for mice. Mice would use logisitic regression for binary and polytomous logistic regression for categorical variables with >2 levels. However, you should not include factors with a lot of levels, saying>30, in imputation models because it would require a lot of dummy variables. Another thing is that not excluding variables you would use in substantive analysis. Otherwise, estimation would be biased. Weidong
On Sat, Nov 26, 2011 at 12:07 PM, Fei <fayechen0807 at hotmail.com> wrote:
Hi Josh, Thanks for the kind reminder of posting the dataframe on. My dataframe contains lots of categorical variables, which seems to be problematic. ?For instance, dob ? ? ? ?status ? ? ? ? edu ? ? ? ? ? ? ? mrext 1111 ? ? ?married ? ? ? highschool ? yes, full time Do you know how to specify the imputation methods and the visitSquence so that those categorical variables are not involved in the imputation process? Thank you. Fei -- View this message in context: http://r.789695.n4.nabble.com/computationally-singular-error-with-mice-tp4109583p4110776.html Sent from the R help mailing list archive at Nabble.com.
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