The term “illegal price manipulation ” is diffi-cult to define. Current U.S. law does not explic-itly define it. The finance and economics litera-ture uses the term “manipulation ” in an impre-cise manner. This paper proposes that a trading strategy not be classified as “illegal price manip-ulation ” unless the violator’s intent is to pursue a scheme that undermines economic efficiency both by making prices less accurate as signals for efficient resource allocation and by making mar-kets less liquid for risk transfer. Since price ef-fects are market-wide, we treat the terms “price manipulation ” and “market manipulation ” as synonyms. Our definition applies equally to fi-nancial and commodities markets.

ABSTRACT Collateral constraints imply that financing and risk management are fundamentally linked. The opportunity cost of engaging in risk management and conserving debt capacity to hedge future financing needs is forgone current investment, and is higher for more productive and less well‐capitalized firms. More constrained firms engage in less risk management and may exhaust their debt capacity and abstain from risk management, consistent with empirical evidence and in contrast to received theory. When cash flows are low, such firms may be unable to seize investment opportunities and be forced to downsize. Consequently, capital may be less productively deployed in downturns.

This paper extends the theory of non‐cash auctions by considering the revenue and efficiency of using different securities. Research on bankruptcy and privatization suggests using non‐cash auctions to increase cash‐constrained bidder participation. We examine this proposal and demonstrate that securities may lead to higher revenue. However, bidders pool unless bids include debt, which results in possible repossession by the seller. This suggests all‐equity outcomes are unlikely and explains the high debt of reorganized firms. Securities also inefficiently determine bidders' incentive contracts and the firm's capital structure. Therefore, we recommend a new cash auction for an incentive contract.

ABSTRACT Patterns in stock market trading volume, trading costs, and return volatility are examined using New York Stock Exchange data from 1988. Intraday test results indicate that, for actively traded firms trading volume, adverse selection costs, and return volatility are higher in the first half‐hour of the day. This evidence is inconsistent with the Admati and Pfleiderer (1988) model which predicts that trading costs are low when volume and return volatility are high. Interday test results show that, for actively traded firms, trading volume is low and adverse selection costs are high on Monday, which is consistent with the predictions of the Foster and Viswanathan (1990) model.

ABSTRACT We analyze a multi‐period model of trading with differentially informed traders, liquidity traders, and a market maker. Each informed trader's initial information is a noisy estimate of the long‐term value of the asset, and the different signals received by informed traders can have a variety of correlation structures. With this setup, informed traders not only compete with each other for trading profits, they also learn about other traders' signals from the observed order flow. Our work suggests that the initial correlation among the informed traders' signals has a significant effect on the informed traders' profits and the informativeness of prices.

We analyze a multi-period model of trading with differentially informed traders, liquidity traders, and a market maker. Each informed trader's initial information is a noisy estimate of the long-term value of the asset, and the different signals received by informed traders can have a variety of correlation structures. With this setup, informed traders not only compete with each other for trading profits, they also learn about other traders' signals from the observed order flow. Our work suggests that the initial correlation among the informed traders' signals has a significant effect on the informed traders' profits and the informativeness of prices.

How does trust evolve in markets? What is the optimal level of regulation and how does this affect trust formation and economic growth? In a theoretical model, we analyze these questions, given the value of social capital and the potential for growth in the market. When social capital is valuable, regulation and trustfulness are substitutes. In this case, regulation may cause lower aggregate investment and decreased economic growth. When the social capital is less valuable, regulation and trustfulness may be complements. In the paper, we analyze the optimal level of regulation and highlight the novel predictions of the model.

This paper uses a nonlinear arbitrage-pricing model, a conditional linear model, and an unconditional linear model to price international equities, bonds, and forward currency contracts. Unlike linear models, the nonlinear arbitrage-pricing model requires no restrictions on the payoff space, allowing it to price payoffs of options, forward contracts, and other derivative securities. Only the nonlinear arbitrage-pricing model does an adequate job of explaining the time series behavior of a cross section of international returns.

To test recent theories suggesting that valuation errors affect merger activity, we develop a decomposition that breaks the market-to-book ratio (M/B) into three components: the firm-specific pricing deviation from short-run industry pricing; sector-wide, short-run deviations from firms’ long-run pricing; and long-run pricing to book. We find strong support for recent theories by Rhodes-Kropf and Viswanathan [2004. Market valuation and merger waves. Journal of Finance, forthcoming] and Shleifer and Vishny [2003. Stock market driven acquisitions. Journal of Financial Economics 70, 295–311], which predict that misvaluation drives mergers. So much of the behavior of M/B is driven by firm-specific deviations from short-run industry pricing, that long-run components of M/B run counter to the conventional wisdom: Low long-run value to book firms buy high long-run value-to-book firms. Misvaluation affects who buys whom, as well as method of payment, and combines with neoclassical explanations to explain aggregate merger activity.