On 9 Mar 2004 06:45:18 -0800, [EMAIL PROTECTED] (Jason Owen) wrote: > Hello, > > An engineering friend of mine has encountered this formula as > a measure of "average" for a sample of N values: > > log (N) - log ( sum (10^-X) ) > > where X is a sample value and log is logarithm base 10. > > Has anyone encountered this before? The closest thing it > resembles is the harmonic mean, but it's certainly not the > same.
- a lot stronger distortion than the harmonic mean - It has the form of a generalized average, for f() equal to exponentiating: inverse-f() of the average of f() . Taking the sum of ten-to-the-<value> does an extreme amount of skewing, if there is any pragmatic range in <value> . If that's the formula, it is an unusual application -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html - I need a new job, after March 31. Openings? - . . ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at: . http://jse.stat.ncsu.edu/ . =================================================================
