Tuesday, April 3, 2012

10:59 PM

Why Google Re-ranks Any Search Results Based upon Time-Based Data in Query Logs


Google has the ability to re-rank search results when those results can be compared to time based data. Or put more simply – Google is able to show you the search pages most historically relevant when you search for a particular term. SEO Positive will try to explain how over the next few paragraphs!

If you look for Wimbledon, which happens every year, when will Google show you the Wimbledon site for this year, or information about this year’s Wimbledon? And why won’t it show you the information for any other Wimbledon –for example one of the famous finals that went on for hours and hours?

The short answer, according to the research done here at SEO Positive, is that Google may internally rewrite your query if it thinks it is likely to have a date attached to it. An implied date, in other words, which you haven’t even bothered to write in because in your head it’s so obvious it doesn’t need specifying.


It’s important to note here – as we have often done at SEO Positive – thatGoogle is trying to act like a human being. And of course when a human asks another human about Wimbledon – if those two people live in the UK, anyway – they are almost certainly talking about the Wimbledon relevant to the current year.

But how does Google know this? Well, the chances are that it looks up common search terms (like “Wimbledon”) and matches them against other queries in a query log. So if you simply type “Wimbledon”, it might look up its query log and see that a lot of other people are typing “Wimbledon 2012”. So it automatically rewrites your query to include date information, and then returns pages most relevant to those dates.

The science behind it is all to do with ratios. There will be an explicit ratio ofsearch terms containing both the current year and the word “Wimbledon”, against the number of queries just containing the word “Wimbledon”, which Google requires its query data to meet before it starts making assumptions. But once that ratio has been satisfied, then Google will automatically assume that all queries containing the word “Wimbledon” actually mean Wimbledon 2012.

The beauty of this is that as the tournament comes and goes, the ratio of queries containing the explicit “Wimbledon 2012” term will diminish – so eventually the next date-specific ratio will take its place.

Here at SEO Positive we’re aware that Google may also pay attention to reformulations of search terms – that is, instances in which an original term was searched for, and then modified with no click through. So if you looked for “Wimbledon”, got your results and didn’t click on anything, then changed the search term to include a year, Google will log that in the query tables it uses to determine whether time based information is relevant to particular classes of query.

The same algorithms may also affect auto fill – hence the range of dates you sometimes see popping up in the drop down menu under your search as you type it.