On 21 Aug 2003 12:54:29 -0700, [EMAIL PROTECTED] (Garbriel) wrote: [ ... ] > > However, there is limitations in this calculation, > > since if X- is zero, so, a21=0, a22=0; > ************************************* > There will appear 0/0. > (and also big problem in p_value calculation). >
Don't you think this is a logical problem rather than a numerical one? - "Not defined" is a pretty good answer. How do *you* describe the correlation of (say) height with weight of a set of objects, where every object is exactly the same height? - well, there is no "co"- variation, so you might settle for zero. But I think that depends on how limited your needs are. -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html "Taxes are the price we pay for civilization." Justice Holmes. . . ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at: . http://jse.stat.ncsu.edu/ . =================================================================
