IST Lunch Bunch

Tuesday May 3, 2016 12:00 PM

Decision making at scale: Algorithms, Mechanisms, and Platforms

Speaker: Ashish Goel, Departments of Management Science and Engineering, Stanford University
Location: Annenberg 105

YouTube competes with Hollywood as an entertainment channel, and also supplements Hollywood by acting as a distribution mechanism.  Twitter has a similar relationship to news media, and Coursera to Universities.  But there are no online alternatives for making democratic decisions at large scale as a society.  In this talk, we will describe two algorithmic approaches towards large scale decision making that we are exploring.

a) Knapsack voting and participatory budgeting: All budget problems are knapsack problems at their heart, since the goal is to pack the largest amount of societal value into a budget.  This naturally leads to "knapsack voting" where each voter solves a knapsack problem, or comparison-based voting where each voter compares pairs of projects in terms of benefit-per-dollar.  We analyze natural aggregation algorithms for these mechanisms, and show that knapsack voting is strategy-proof.  We will also describe our experience with helping implement participatory budgeting in close to two dozen cities and municipalities, and briefly comment on issues of fairness.

b) Triadic consensus: Here, we divide individuals into small groups (say groups of three) and ask them to come to consensus; the results of the triadic deliberations in each round form the input to the next round.  We show that this method is efficient and strategy-proof in fairly general settings, whereas no pair-wise deliberation process can have the same properties.

This is joint work with Tanja Aitamurto, Brandon Fain, Anilesh Krishnaswamy, David Lee, Kamesh Munagala, and Sukolsak Sakshuwong.

Series IST Lunch Bunch

Contact: Diane Goodfellow at 626-395-6842 diane@cms.caltech.edu