Northwestern CS Theory and Economics Ph.D. student Manolis Pountourakis did a really fantastic job of presenting his paper Optimal Auctions vs. Anonymous Pricing (joint with with coauthors Saeed Alaei, Rad Niazadeh, Yang Yuan, and me). The paper proves that eBay’s Auctions and Buy-It-Now (posted pricings) are within at least an e = 2.718 factor of the revenue optimal auction (which may be asymmetric and very complicated). This is a worst-case bound that is quite difficult to prove; in practice the eBay’s sales mechanisms likely do much better. Watch the video!
TCS Prof. Anindya De presented his paper Beyond the central limit theorem: Asymptotic expansions and pseudorandomness for combinatorial sums. This paper extends the central limit theorem to achieve faster convergence rates by using information about a large number of moments of the sum (as opposed to just the mean and variance). This result also has applications in space bounded derandomization, a central question in complexity theory. Watch the video!