Why a the Sitemaps query stats may say you come up for a popular term even though you don't mention that term or phrase on your pages of your site?
This was one of the primary questions raised by David Naylor hwen he posted the two tests on his blog to prove the fallibility of Google Sitemaps.
Vanessa Fox of Google Engineering responded to the query. You can't miss the details. So there they are-
(1) Stats are based on three week averages; "They are averaged over a three week period, so any big fluctuations during that period may make the stats seem off."
(2) "They are top overall queries. For instance, say your site isn’t about Britney Spears, but you’ve mentioned her a few times and so your site ranks for her (although likely doesn’t rank well). Your site is actually about purple apples. So, if a million people search for Britney and 10 people search for purple apples, then Britney is going to show as a top query. And you might look at that and say, my site isn’t even about her. How can that query be higher for my site than what my site is actually about? But in sheer number of searches, Britney is a top query for the site."