Computational advertising is a new scientific sub-discipline, at the intersection of information retrieval, machine learning, optimization, and microeconomics. Its central challenge is to find the best ad to present to a user engaged in a given context, such as querying a search engine (“sponsored search”), reading a web page (“content match”), watching a movie, and IM-ing. http://research.yahoo.com

Match Game

Imagine reading an ESPN blog post about pro golfer Tiger Woods and seeing a short ad for the San Francisco Zoo displayed on the same page. Or imagine the horror of reading a lurid news item about a headless body found in a suitcase—and then seeing an advertisement for a leading luggage manufacturer. Not the best way to win friends and influence sponsors.

It’s no secret that online ads should correspond to the pages on which they appear. After all, relevant ads ensure a better user experience and increase the likelihood of clickthroughs.

The problem, however, is that conventional ad matching techniques do not always produce the most reliable results. That’s why Yahoo! Research scientists Andrei Broder, Marcus Fontoura, Vanja Josifovski, and Lance Riedel developed a new approach, which is highlighted in their research paper titled “A Semantic Approach to Contextual Advertising.”

Previous approaches matched ads based on the appearance of the same words or phrases within both the ad and the webpage. For instance, a news story about the Wimbledon tennis tournament could feature contextual ads with terms like “tennis racquet” or “tennis balls”.

But what if the webpage and the ad use different words to describe the same thing? In this scenario, an ad containing the word “physician” might not be matched with a webpage about “doctors.”

To rectify the problem, Yahoo! researchers are developing a mechanism that not only matches ads based on keywords, but also on overall concepts that are more general than specific words. “Basically, the crucial idea we want to convey is that words matter, but understanding what the page is about matters more,” says Broder.

Continues @ http://research.yahoo.com/node/2145