I need to build a logistic regression model. there are around 50 categorical variables. So, is this approach to select variables wrong?: do a chi square test of dependent variable vs independent variables, and only use those variables which show a dependency (p value lesser than .05). similarly using t test to see if continuous variables are actually different when why dependent variable is either 0 or 1.
or kindly tell how can this approach go wrong (data has got around 2000 rows, so less observation wont be a problem for sure.)