How to use the Google “Query Deserves Freshness” or QDF model to your advantage

  • 1
  • December 3, 2007
Patrick Altoft

Patrick Altoft

Director of Strategy

The Query Deserves Freshness or QDF algorithm was first discussed by Amit Singhal in a New York Times article about the Google Algorithm in June. During the second half of 2006 Google was trying to figure out a way of showing new content for some “hot” search terms while keeping the more competitive keywords spam free.

The issue came to a head when Google Finance was launched and didn’t rank for its own name.

Freshness, which describes how many recently created or changed pages are included in a search result, is at the center of a constant debate in search: Is it better to provide new information or to display pages that have stood the test of time and are more likely to be of higher quality? Until now, Google has preferred pages old enough to attract others to link to them.

The problem is that Google has to give more weight to older content to keep the quality of the search results high. The solution is a mathematical model that tries to determine when users want new information and when they don’t.

THE QDF solution revolves around determining whether a topic is “hot.” If news sites or blog posts are actively writing about a topic, the model figures that it is one for which users are more likely to want current information. The model also examines Google’s own stream of billions of search queries, which Mr. Singhal believes is an even better monitor of global enthusiasm about a particular subject.

As an example, he points out what happens when cities suffer power failures. “When there is a blackout in New York, the first articles appear in 15 minutes; we get queries in two seconds,” he says.

Mr. Singhal says he tested QDF for a simple application: deciding whether to include a few news headlines among regular results when people do searches for topics with high QDF scores. Although Google already has a different system for including headlines on some search pages, QDF offered more sophisticated results, putting the headlines at the top of the page for some queries, and putting them in the middle or at the bottom for others.

The QDF model takes a number of factors into account, including:

  • Search volume
  • News coverage
  • Blog coverage
  • Toolbar data (maybe)

Google has a patent on the methods they use to gather this data including a sampling technique that allows them to gather statistically accurate data without having to trawl through all the logs for a particular query.

QDF is clearly a very interesting model but what really interests me is how I can use it to drive traffic to my websites. This is where the Hot Topics tool comes in.

As you might have guessed QDF is a great way for newer sites to publish content and leapfrog the Google trust filter for queries that Google thinks are fresh. The key is to post about breaking news stories as soon as possible, hope Google indexes your story quickly and watch the traffic come rolling in. Once your site ranks highly it becomes a self reinforcing authority and is referenced by other people researching the topic.

So, next time you are stuck for something to write about make sure you choose something fresh. Find something people are blogging about and searching for in much greater numbers than last week.

A good example today is the search for “canoeist” which is probably a very low volume term. Today thousands of people are searching for information about the canoeist who went missing 5 years ago and turned up in London at the weekend. The search results are now full of references to this new story. Notice how Google has given higher rankings to stories released within the last 2 days whereas other articles about canoeists from very well trusted sites are down on page 2 and 3.