Dear Jens Henrik thank you very much! It seems very interesting. I will try to install it at once. Giovanni -- Giovanni M. Marchetti <giovanni.marchetti at unifi.it> Dipartimento di Statistica, "G. Parenti", Universita' di Firenze viale Morgagni, 59 Phone: +39 055 4237 204 I 50134 Firenze, Italy Fax: +39 055 4223 560