why are empty cells in a regression how to regress on a nonnormal dependent variable what trtile is used to regress a non normal variable how do you regress on a variable that is not considered normal what is the normal distribution of residuals what variable are n-tiles what is a normal residual in a regression? can regression be done with non normal variable can you use quintiles on independent variable what type of model would use quintiles which variables are used in a nonlinear regression? why can't you regress on a nonnormal variable with less covariates why are empty cells important when regressing on nonlinear variables what are the results when do you use quintiles in a regression? how to perform a regression on a non normal conditional variable what type of regression is using quintiles what is normal regression what to use to do an ordinal regression what is tertiles in regression