NYCE 2009

NY Area CS and Economics (NYCE) II meeting took place on Monday, Nov 6, and was organized by Robert Kleinberg and Eva Tardos.

• Jennifer Rexford led and spoke about interdomain routing in IP networks. She started with a simple model of local rules for path selection that converge to stable paths for routing between IP domains, and later generalized it to picking multiple paths via source dependent path selection. She is an admirably clear speaker on a topic with many details (original RFC here). There were many questions on machine learning (are there algorithms to learn the ``value'' of paths), technology (how to simulate these policies by say MPLS protocols), incentives (domains choosing cheap paths over secure paths, fishing for information via strategic path announcements), and verifiability (can routers send traffic on whatever path they choose despite what they advertise).
• Shahar Dobzinski spoke about truthful polytime approximate mechanisms for multiunit auctions. This was classic AMD material, delivered straight. Questions explored monotonicity (eg quasi-monotonic valuations such as cant use >10k oil barrels) and variance of allocation.
• Michael Kearns showed his theory roots and applied arms. He spoke about matching buy and sell orders, not in light pools where the book shows bid and ask prices, but in the dark pools where only liquidity counts. He proposed an exploration-exploitation approach to buy large orders in dark polls, ultimately deriving RL type algorithms. Questions included role of Crypto protocols (not a good idea to enforce trust, better to remove conflicts in the system design), Strategic orders (to sniff information), and quality of price in light pools (since dark pools set price using light pools but their demand and supply are not reflected in the price at light pools), etc.
  
• Lunch in the financial district is always an exercise in avoiding crowds.
  
• Post lunch, there was a rump session of 5-min talks. Beibei Li spoke about ranking hotels by mining web data. Sharad Goel spoke about pricing ads per impression plus a click cost. Eyal Carmi spoke about quantifying derived effects on an item of a sudden spike in popularity of a related item. Mickey Brautbar spoke about algorithms for finding nodes with high degree (why these are "interesting individuals" is presumably discussed in their ICS paper?). Aaron Jaggard spoke about impossibility results for distributed decisions, from here. Vahab Mirrokni gave a clear talk on quasi-proportional mechanisms and their equilibrium revenue properties. Ruggiero Cavallo spoke about limited amount altruism in auctions. Other talks discussed social network effects to long tail phenomenon.
  
• Larry Blume gave the final talk. He started with several simple examples where we reason about probability, but implicitly with different meanings. He then formally defined different measures of ``probability'' and "expected utilities" including non-additive ones, and worked into applying them to Economic choices agents make. I was overwhelmed by the rich notions of rationality in Economics, and would like to work out some nontrivial examples of applications of these concepts. I liked the narrative in this talk, and Larry is consummate researcher switching between Math and insights, with anecdotes as needed.
  

One of the interesting aspects of NYCE is the audience from business schools to, as it turned out, businesses. The NY Academy of Sciences venue is superb, and the staff run the meeting smoothly.