Dear Marc Schwartz,
Thanks for your help! I appreciate it very much. I was reading "Modern Applied Statistics with S-plus" by W.N. Venables and B.D. Ripley (second edition, 1997) page 209 for similar problem which was a bit unclear to me (may be this is becase i'm a total newbie; but don't worry: i understood what is a *Frame* from "The Basics of S and S-plus" by A. Krause and M. Olson page 44-47 :) ); but your discussion made it *all* clear. Also, thanks for those web addresses. It was very helpful. Ehsan _______________________ Mohammad Ehsanul Karim <[EMAIL PROTECTED]> Institute of Statistical Research and Training University of Dhaka, Dhaka- 1000, Bangladesh ________________ . . ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at: . http://jse.stat.ncsu.edu/ . =================================================================
