Playing with a system is a great way to get some insight and ultimately find the important problems to solve. In internet ad auctions, it is easy to experiment as an advertiser. For example, if you search for FOCS 2008 (or Piotr Indyk or Muthukrishnan or ..) in Google, you find variations of the following ad (run by one you can also find by searching for Ronitt):
You can get valuable experience then looking at the clicks and impressions. The more difficult issue to get experience in being a publisher who shows ads from different sources. OpenX now gives an open source platform to play the publisher, wonder if it will be useful to the academic community for experimenting.
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