Different results in Altavista, MSN & Yahoo!
Different results in Altavista/MSN/Yahoo!
A team member of ours did some checking recently comparing results between Yahoo! and its search subsidiaries and found some interesting results. So much so that it begs the question: Why are there different results between the sites?
I am talking about the differences you may have noticed between Yahoo! and the sites it provides results for. Namely Altavista, Alltheweb and MSN. If you do the same search across these different engines, chances are good that you get different results. This doesn’t make sense considering that Yahoo! is supposed to be supplying the search results to these sites. If this is the case, you would expect that all four sites should have the same results, right? Wrong.
Why you ask? Well, it comes down to the algorithms.
When we were checking results against the sites, we were finding differences not only in the rankings, but also with the number of pages indexed and the number of pages per site indexed. But we are only going to be dealing with rankings here.
As you may already know, all of the major search engines have different algorithms. The algorithms determine how the pages will rank depending on a variety of factors including OTP (On The Page) factors, such as title tags, descriptions, body text, page length etc. as well as other factors including link relevancy and inheritance to name just a few.
The combinations of these factors, along with the weightings each engine puts on them, coalesce to make up the ranking algorithm which determines where pages will show up in the search results. These ranking algorithms are controlled by the independent engines. And this is why the search results appear differently across multiple engines.
What is happening is that Yahoo! is merely providing the index, or list of sites. They are saying, “Hey MSN, here you go. Here is the list of sites we have added in our index, now it is up to you to rank them the way you see fit.”
It would be like giving someone a deck of cards. Usually, if they are not new, they are in random order. Now if you handed the cards to 3 different people and asked them to organize them, chances are each person would organize them differently. You could organize them by suit, or by face value, or by some combination of these. Ultimately each person would likely organize them differently. If you then asked them to pull the 20th card from the deck, there is a good chance that they would each draw different cards as the decks are organized different.
This is how the algorithms work. Each engine determines how to order the results based on the factors mentioned above. Therefore while the Yahoo! index may be the same across the board for each site, the final search results will be different.
Just so you know, in our test of about 50 sites, there was sometimes over 1000-page differences in rankings. That means, for example, that a site could rank in the top 10 in MSN and not even be in the top 1000 in Altavista (or vice versa). There were some results displayed where rankings were within a few positions, while others were thousands apart. This difference is due to the ranking algorithms.
So, if you think your site will do well in MSN or Altavista just because you are doing well in Yahoo! don’t be so sure. Conversely, if you find you are ranking lower than you like in Yahoo! don’t assume that you are also ranking low in one of the other engines because it is entirely dependant on the engine.
Author Bio:
Rob Sullivan
Production Manager
Searchengineposition.com
Search Engine Positioning Specialists
