On Sun, 7 Nov 2010 09:39:10 +0000, Malcolm
wrote:


In article ,
writes
On Sat, 6 Nov 2010 18:48:42 +0000, kay
wrote:


But many
analyses are simply looking at presence or absence of a species, and
actual numbers are irrelevant to this.


But only in participating gardens. That cannot be extended to whole
populations throughout the country, for the reasons I have given.

Your "reasons" are flawed because you don't (?won't, ?can't) understand
the concept of sampling.

Don't try to make it sound difficult, Malcolm :-)