how to do a panel ols when is a sur data used? why not what are two different variables used in OLs when do asur data have to be stacked what if ols is different from sur can you ols a panel data when does an OLS work for multiple years why do OLs run different panel data how to run ols on multiple panels what type of data do panel data with different variables use aggregator how to run ols how do you run the ols when to run ols on different variables how to separate data in survey data how to do ols why can't i do a ols on panel data why does ols stand for layered data what are the different variables in a panel of data that can be stacked vertically in ols when to use OLS or sur why do you need two variables in the same OLS