A sequence of previous papers has demonstrated that a genetic algorithm (GA) can be used to automatically discover new optimal auction mechanisms for automated electronic marketplaces populated by software-agent traders. Significantly, the new auction mechanisms are often unlike traditional mechanisms designed by humans for human traders; rather, they are peculiar hybrid mixtures of established...

Tirole (1982) is commonly interpreted as proving that bubbles are impossible with finitely many rational traders with common priors. We study a simple variation of his model in which bubbles can occur, even though traders have common priors and common knowledge that the asset has no fundamental value. In equilibrium, agents purchase the asset at successively higher prices until the bubble "burs...

We study the optimal placement problem of a stock trader who wishes to clear his/her inventory by a predetermined time horizon t, by using a limit order or a market order. For a diffusive market, we characterize the optimal limit order placement policy and analyze its behavior under different market conditions. In particular, we show that, in the presence of a negative drift, there exists a cri...

We consider the hedging error of a derivative due to discrete trading in the presence of a drift in the dynamics of the underlying asset. We suppose that the trader wishes to find rebalancing times for the hedging portfolio which enable him to keep the discretization error small while taking advantage of market trends. Assuming that the portfolio is readjusted at high frequency, we introduce an...

Market-makers serve an important role as providers of liquidity and order in financial markets, particularly during periods of high volatility. Optimal market-makers solve a sequential decision making problem, where they face an exploration versus exploitation dilemma at each time step. A belief state MDP based solution was presented by Das and Magdon-Ismail [2008]. This solution however, was c...

The purpose of market design is to increase the efficiency of the market outcome by suppressing strategic behavior or rendering it ineffective. One part of this task is to eliminate loopholes in the procedural rules that might be exploited by a wily trader, but the more fundamental part is to devise rules that promote efficiency. In the case of an iterated multi-market auction, the key requirem...