I am not able to understand that why there is a difference in position of my website with same keywords in google.com and google.ca. On google.com my site is at 7th position with a keyword and with that same keyword it is at 5th page in google.ca. Can anyone here tell me the reason please? Your answers and experiences are most welcome, so please share.
Please check below URL:
http://www.google.com/support/forum/p/Webmasters/thread?tid=42f5c909eeafe77c&hl=en
There are several factors that it could be.
If you are logged into one site but not the other (which often happens if you are testing in different browsers), that will almost certainly affect how your site ranks. Google will personalise the search results to make them the best it can for you, based on what it knows about your searching and browsing habits. Your site will generally rank higher up when you are logged in, because the chances are you visit it more often than the average person would - Google knows you go to it a lot so pushes it higher up the list.
The reason for having different country domains (apart from switching the language in some cases) is to allow results to be reordered as appropriate to that country. If your site ranks better on google.ca than it does on google.com, that means that Google thinks your site will be relatively more useful to people in Canada than elsewhere. Obviously, there is more competition for global search than country specific search, so it is a bit easier to secure a good place on the national searches than on .com
And finally, there is a random element to the results. Algorithms are constantly being tweaked, factors taken into account, indexes updated and so on. Your search query will be sent to any one of many Google computers, and some of them might be running slightly different versions of the search algorithm. Even if all the other factors are exactly equal, you can run the same query and get slightly different results, just because of the randomness and changes that you don’t get to see or have any control over.