The  Weizmann  Institute  of  Science
                  Faculty of Mathematics and Computer Science


             Walmart Lecture Series in Cryptography and Complexity

                     Lecture Hall, Room 1, Ziskind Building
                            on Sunday, May 29, 2011
                                 11:00 - 12:30





                                 Jason Hartline
                            Northwestern University


                                 will speak on


                      The Theory of Crowdsourcing Contests

Abstract:
Crowdsourcing contests have been popularized by the Netflix challenge and
websites like TopCoder and Taskcn.  What is a crowdsourcing contest?
  Imagine you are designing a new web service, you have it all coded up, but
the site looks bad because you haven't got any graphic design skills.  You
could hire an artist to design your logo, or you could post the design task as
a competition to crowdsourcing website Taskcn with a monetary reward of \$100.
Contestants on Taskcn would then compete to produce the best logo. You then
select your favorite logo and award that contestant the \$100 prize.

In this talk, I discuss the theory of crowdsourcing contests.  First, I will
show how to model crowdsourcing contests using auction theory.  Second, I will
discuss how to solve for contestant strategies.  I.e., suppose you were
entering such a programming contest on TopCoder, how much work should you do on
your entry to optimize your gains from winning less the cost of doing the
work?  Finally, I will discuss inefficiency from the fact that the effort of
losing contestants is wasted (e.g., every contestant has to do work to design a
logo, but you only value your favorite logo).  I will show that this wasted
effort is at most half of the total amount of effort.  A consequence is that
crowdsourcing is approximately as efficient a means of procurement as
conventional methods (e.g., auctions or negotiations).

Joint work with Shuchi Chawla and Balu Sivan.