Alan writes
In message , SimplyGardening
wrote

Based on a sample of how many?

122,000 visitors in total

I bet they didn't survey everyone.

No need to if all you want to find out is the general characteristics of
a 'population' (in this case the population is made up of those who
visit the show).

If you pick a sample of two, say, and find the average income is
£40,000, then picking a third person and finding their income is £10,000
severely affects your calculated average.

But if you've calculated your average of £40,000 on a sample of 500, the
fact that number 501 comes along with an income of only £10,000 isn't
going to make a lot of difference.

What I'm puzzled about is why we should be interested in the
characteristics of the visitors to the show in the context of some guy
trying to flog a garden that he hasn't yet built.


--
Kay