Dear all, I'd like to ask if it would be a good idea to add an extra argument to 'optim' (with default value NULL) to give a initial Hessian for the BFGS algorithm. This could be handy in some cases where this initial approximation is available and thus it isn't required 'optim' to compute it again. Thanks for any comments, Dimitris ---- Dimitris Rizopoulos Ph.D. Student Biostatistical Centre School of Public Health Catholic University of Leuven Address: Kapucijnenvoer 35, Leuven, Belgium Tel: +32/16/336899 Fax: +32/16/337015 Web: http://www.med.kuleuven.ac.be/biostat/ http://www.student.kuleuven.ac.be/~m0390867/dimitris.htm