Peter Lachenbruch wrote:
>Perhaps a na�ve approach would be to bootstrap the cv with a few thousand reps. An obvious problem arises if the mean is near 0. >I suspect one should restrict this to positive random variables, but I have no theory to go on.
Seems right to me. CV is meaningful for a ratio scale variable (e.g., mass, time, distance) but not an interval one (e.g,. Celsius temperature, utility). While it is, of course, possible to define a signed ratio scale, the vast majority of them are non-negative.
*
* For searches and help try:
* http://www.stata.com/support/faqs/res/findit.html
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
