Bill Slawski at Search Engine Lands, after reading a WWW 2007 paper that classifies search engine queries, notes that "most queries are noncommercial."
These queries pose a problem for advertising. What do you advertise on web pages or queries that have no commercial intent?
There appear to be two approaches: (1) Target ads anyway, doing the best job we can. (2) Look elsewhere for commercial intent.
Most web advertising today uses the first method, target the ads anyway, sometimes with hilarious consequences. For example, Google AdSense, on news stories about immigrant trafficking, has been known to show ads for boat rentals and other services that might assist in immigrant trafficking. A news story I just saw about a plane crash was showing ads for firefighting equipment and surplus army MREs.
Given the lack of commercial intent on these queries, it is hard to do better. What ads should we show next to an article about a plane crash or immigrant trafficking? Is anything really appropriate?
Perhaps not. That is where the second approach comes in. What if we look elsewhere for commercial intent instead?
Personalized advertising is not just about showing different advertising to different people. Personalized advertising often requires maintaining a history of what someone has done recently.
In this recent history, there will be items that have strong commercial intent, in many cases, much stronger commercial intent than the current page. We are reaching back into the history to target the ads might be more appropriate than targeting to the current page.
For example, let's say I just looked at a review of a car, then looked at a news article about a plane crash. One of these actions shows strong commercial intent, the other does not. We can target ads easily to the car review, but not to the plane crash.
At the moment, newspapers, weblogs, and other web sites have great content, but difficulty monetizing that content. This is because much of the content reveals little or no information about the commercial intent of the people viewing the content. Ads targeted to those pages are often ineffective and, because of the lack of commercial intent, probably will continue to be no matter how much content targeting improves.
Personalized advertising reaches back into the past, looking for something that has commercial intent. Rather than attack the problem of divining commercial intent where their is none, personalized advertising tackles the much easier problem of recalling past actions that do show strong commercial intent.
Surprisingly, at least to me, there appear to be few examples of personalized advertising systems that attempt fine-grained targeting to recent history. Findory attempted to build one that targets to content in your Findory history. Amazon built Omakase, which targets to items in your Amazon purchase and viewing history.
Most other attempts at personalized advertising appear to target to high-level subject interests or demographics, not to recent history. They are missing the opportunity to find commercial intent in what I did recently rather than what I am doing now.