Settling the Complexity of Arrow-Debreu Equilibria in Markets with Additively Separable Utilities

We prove that the problem of computing an Arrow-Debreu market equilibrium is PPAD-complete even when all traders use additively separable, piecewise-linear and concave utility functions. In fact, our proof shows that this market-equilibrium problem does not have a fully polynomial-time approximation scheme unless every problem in PPAD is solvable in polynomial time. ∗ Department of Computer Science, Princeton University. † Department of Computer Science, Tsinghua University. Work done while visiting Princeton University. This work was supported in part by the National Natural Science Foundation of China Grant 60553001, and the National Basic Research

• Type: Conference
• Year: 2009
• Where: FOCS
• Authors: Xi Chen, Decheng Dai, Ye Du, Shang-Hua Teng
• Keywords: FOCS 2009, Fully Polynomial-time Approximation Scheme, National Natural Science Foundation Of China, Princeton University, Theoretical Computer Science