Can we use ordinal/multilevel predictors directly into binary logistic regression model?
I guess not.
we usually here convert them to multiple predictors to have values 1/0 for each category.
Also if we have a variable with say 20 levels(e.g. sectors like 'energy' 'IT' 'telecom') or factors, should we created 20 variables with values 1/0 for each type or is there better way?