Dear All, I have to add to my recent request that the independent variables that I want to add to the existing 54 independent variables are unit-invariant (only time varying) macroeconomic variables. Only if they are unit-invariant one of the time-dummies is omitted. It actually does not omit the time dummy when I add a time-varying and unit-varying variable. My question is why is a time dimension/time dummy omitted as one unit-invariant time-varying variable is added? Many thanks and best regards. Nicolai ___________________________________ Nicolai Striewe Research Assistant Real Estate Management Institute Aareal Professorship Real Estate Banking Department of Finance, Accounting and Real Estate European Business School (EBS) Greater Frankfurt GERMANY -----Ursprüngliche Nachricht----- Von: Nicolai C. Striewe [mailto:Striewe.ebs@rem-institute.org] Gesendet: Mittwoch, 13. Mai 2009 14:55 An: 'gretl-users(a)lists.wfu.edu' Betreff: Limited Number of Independent Variables - Random Effects - Panel Data Dear all. May I pose the following problem with the random-effects panel data model that I created: The model consists of 54 independent variables (1 constant, 8 focus variables, 5 control variables, and 40 time dummies). When I extend the model by one focus variable it cuts off one time dummy. It seems to be a restriction of gretl, that if more than 54 variables are specified in the model, gretl leaves out all independent variables exceeding this limit without a notification of omitting some variables. Does gretl restrict the number of independent variables to 54? If yes, is there a way around that restriction? Many thanks in advance for your comments and thoughts. Best regards, Nicolai Striewe ___________________________________ Nicolai Striewe Research Assistant Real Estate Management Institute Aareal Professorship Real Estate Banking Department of Finance, Accounting and Real Estate European Business School (EBS) Greater Frankfurt GERMANY