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***** Exercise - Logistic regression *****
***** Vu Dien - Jun 25, 2013 *************


*using insheet to input data from txt file* 
*need to change directory before running the below command*
insheet newpid ht sex age religion duradm smoke bmigroup bmi a1cyn bpyn ldlcyn all3g any3g using exercise_logistic_reg.txt

*cross tabulate ht with each to see which is the most promising*
tabulate ht a1cyn
tabulate ht bpyn
tabulate ht ldlcyn

tab a1cyn ht, col

*study effect*
logistic a1cyn i.ht

*covariates*
logistic a1cyn i.smoke
logistic a1cyn bmi

*full model*
logistic a1cyn i.ht bmi i.smoke