Dear Colleagues: I have recently begun using R in my personal research. I have a pair of bivariate probit models that I have already estimated in Stata (v. 8.0) that I am trying to replicate in R. I have been able to replicate the first Biprob using R that is run on a Windows based system. However, the Windows based system does not have enough RAM to run two Biprobs and then generate an ROC curve comparing the fitted values. I have been able to access the university's mainframe through the help of a professor in my department. However, to run R (version released on 8/25) on the university mainframe I need to use Linux. I have been able to load the data into the system. However, when I try to run the same Biprob model(the one I replicated earlier on the Windows system) it runs the VGAM prompts and then I get the following error command: Error: incorrect number of subscripts on matrix What I need to do is run to different bivariate probits and then have R generate a ROC curve comparing the results of the two different models. Please help me to overcome this error problem. Thanks for your time. Anessa L. Kimball Anessa L. Kimball Binghamton University PhD Candidate, Department of Political Science - Zelig Mailing List, served by Harvard-MIT Data Center Send messages: zelig(a)latte.harvard.edu [un]subscribe Options: http://lists.hmdc.harvard.edu/?info=zelig Zelig program information: http://gking.harvard.edu/zelig/