by darryl » Sun Mar 04, 2012 6:19 pm
It could, but it doesn't because people are often unclear on what they exactly mean about an 'overall' number, and how you would get that value depends on how you've done the sampling in the first place, what covariates you've got info on from both the sampled, and unsampled places within your population of interest etc. Search the forum (and may the MARK and RMARK forums too) for phrases like "overall psi" and you should come across some of the previous discussion.
Cheers
Darryl