Computer Science Department
School of Computer Science, Carnegie Mellon University
Luis von Ahn
I introduce three other examples of "games with a purpose": Peekaboom, which helps determine the location of objects in images, Phetch, which collects paragraph descriptions of arbitrary images to help accessibility of the Web, and Verbosity, which collects "common-sense" knowledge.
In addition, I introduce CAPTCHAs, automated tests that humans can pass but computer programs cannot. CAPTCHAs take advantage of human processing power in order to differentiate humans from computers,an ability that has important applications in practice.
The results of this thesis are currently in use by hundreds of Web sites and companies around the world, and some of the games presented here have been played by over 100,000 people. Practical applications of this work include improvements in problems such as: image search, adult-content filtering, spam, commonsense reasoning, computer vision, accessibility, and security in general.