Hello!
I want to control for education in a OLS regression. Right now I have all of my data in a single education variable.

1. Does it make sense to divide it in 2 dummies: secondary school and college, and include both on the regression? Or do I do both of them together as 1 dummy only? Is there any difference?
2. If I do the 2 dummies (with values of eitheir 1 or 0) do I have to put as missing values the college data in the secondary school dummy variable or can it be the zero (0). The same for the college dummy variable, is it ok that the secondary school data is coded as zero?

Thank you