6.6.2.2.4.1.2. statsmodels.sandbox.panel.mixed.Unit.compute_P

Unit.compute_P(Sinv)

projection matrix (nobs_i, nobs_i) (M in regression ?) (JP check, guessing) Display (3.10) from Laird, Lange, Stram (see help(Unit))

W - W X Sinv X’ W’