Approximating Walrasian Equilibria

Approximating Market Equilibria

In this paper we consider the classic problem of finding the market equilibrium prices under linear utility functions. A notion of approximate market equilibrium was proposed by Deng, Papadimitriou and Safra [5]. Using this notion, we present the first fully polynomial-time approximation scheme for finding a market equilibrium price vector. The main tool in our algorithm is the polynomial-time ...

On the Equivalence of Walrasian and Non-walrasian Equilibria in Contract Markets: Complete Contracts

This paper explores two models of an economy in which contracts are exchanged. In the rst version contracts are exchanged on a competitive market in which traders expectations concerning conditions that prevail within specic markets adjust until markets`clear'. In the second model contract designers compete directly against one another by oering alternate contracts. It is shown that the two mod...

The Computation of Counterfactual Equilibria in Homothetic Walrasian Economies

From singularity theory to finiteness of Walrasian equilibria

The paper establishes that for an open and dense subset of smooth exchange economies, the number of Walrasian equilibria is finite. In particular, our results extend to non-regular economies; it even holds when restricted to the subset of critical ones. The proof rests on concepts from singularity theory.

Computing Walrasian Equilibria: Fast Algorithms and Structural Properties

We present the first polynomial time algorithm for computing Walrasian equilibrium in an economy with indivisible goods and general buyer valuations having only access to an aggregate demand oracle, i.e., an oracle that given prices on all goods, returns the aggregated demand over the entire population of buyers. For the important special case of gross substitute valuations, our algorithm queri...