This paper concerns a decision problem of an agent, searching to find a low price, whose memory is represented by a partition of the set of possible past prices. The number of elements in the partition is limited. I characterize the optimal partition for the case of a single decision, and then consider memory allocation among several decisions. I consider a case in which a consumer who must allocate a single bit of memory among two decision problems would do better to allocate it exclusively to one of the problems than to use it to convey joint information about both.

Existing research on chief executive officer (CEO) turnover focuses on CEO ability. This paper argues that board ability is also important. Corporate boards are reluctant to replace CEOs, as this makes financing expensive by sending a negative signal about board ability. Entrenchment in this model does not result from CEO power, or from agency problems. Entrenchment is mitigated when there are more assets-in-place relative to investment opportunities. The paper also compares public and private equity. Private ownership eliminates CEO entrenchment, but market signals improve investment decisions. Finally, the model implies that board choice in publicly listed firms will be conservative.

This paper presents an equilibrium model of the federal funds market that ties movements in the funds rate to changes in the supply of reserves and to a fixed cost facing banks that borrow at the discount window. It is found that the existence of the fixed cost is capable of explaining a number of features of the funds market. In particular, it is critical for explaining occasional instances of extremely high funds rates. It also provides an explanation for heterogeneous behavior across banks towards the discount window and for higher average funds rates at the end of maintenance periods.

A privately informed trader will engage in costly arbitrage, that is, trade on his knowledge that the price of an asset is different from the fundamental value if: (1) his order does not move the price immediately to reflect the information; and (2) he can hold the asset until the date when the information is reflected in the price. We study a general equilibrium model in which all agents optimize. In each period, there may be a trader with a limited horizon who has private information about a distant event. Whether he acts on his information, and whether subsequent informed traders act, is shown to depend on the possibility of a sequence or chain of future informed traders spanning the event date. An arbitrageur who receives good news will buy only if it is likely that, at the end of his trading horizon, a subsequent arbitrageur's buying will have pushed up the expected price. We show that limited trading horizons result in inefficient prices, because informed traders do not act on their information until the event date is sufficiently close. We also show that limited horizons can arise because of the cost‐carry associated with holding an arbitrage portfolio over an extended period of time.

In a capitalist economy prices serve to equilibrate supply and demand for goods and services, continually changing to reallocate resources to their most efficient uses. However, secondary stock market prices, often viewed as the most 'informationally efficient' prices in the economy, have no direct role in the allocation of equity capital since managers have discretion in determining the level of investment. What is the link between stock price informational efficiency and economic efficiency? We present a model of the stock market in which: (i) managers have discretion in making investments and must be given the right incentives; and (ii) stock market traders may have important information that managers do not have about the value of prospective investment opportunities. In equilibrium, information in stock prices will guide investment decisions because managers will be compensated based on informative stock prices in the future. The stock market indirectly guides investment by transferring two kinds of information: information about investment opportunities and information about managers' past decisions. The fact that stock prices only have an indirect role suggests that the stock market may not be a necessary institution for the efficient allocation of equity. We emphasize this by providing an example of a banking system that performs as well.

Do more talented traders prefer to bet on and against rare events or common events? Bets on rare events include out of the money options. Bets against rare events include the carry trade and investment grade bonds. In a model where traders specialize, equilibrium pricing reflects trading ability: A market with more skilled traders has a larger bid ask spread. We show that lower skill traders bet on and against rare events, while higher skill traders bet on and against frequent events, leading to higher bid-ask spreads in common event assets, and reducing financial markets’ ability to predict rare events.

When should we expect bubbles? Can levered intermediaries bid up risky asset prices through asset substitution? We study an economy with financial intermediaries that issue debt and equity to buy risky assets. Asset substitution alone cannot cause bubbles because it is priced into the intermediaries׳ securities. But incomplete contracts and managerial agency problems can make intermediaries take excessive risk to exploit limited liability, bidding up risky asset prices. This destroys welfare through misallocation of resources. We argue that incentives for private monitoring cannot solve this problem. Finally, even without agency problems, debt subsidies will create similar effects.

A privately informed trader will engage in costly arbitrage, that is, trade on his knowledge that the price of an asset is different from the fundamental value if: (1) his order does not move the price immediately to reflect the information; and (2) he can hold the asset until the date when the information is reflected in the price. We study a general equilibrium model in which all agents optimize. In each period, there may be a trader with a limited horizon who has private information about a distant event. Whether he acts on his information, and whether subsequent informed traders act, is shown to depend on the possibility of a sequence or chain of future informed traders spanning the event date. An arbitrageur who receives good news will buy only if it is likely that, at the end of his trading horizon, a subsequent arbitrageur's buying will have pushed up the expected price. We show that limited trading horizons result in inefficient prices, because informed traders do not act on their information until the event date is sufficiently close. We also show that limited horizons can arise because of the cost-carry associated with holding an arbitrage portfolio over an extended period of time.

We consider a model of the stock market with delegated portfolio management. Managers try, but sometimes fail, to discover profitable trading opportunities. Although it is best not to trade in this case, their clients cannot distinguish “actively doing nothing,” in this sense, from “simply doing nothing.” Because of this problem, (i) some portfolio managers trade even though they have no reason to prefer one asset to another (noise trade). We also show that (ii) the amount of such noise trade can be large compared to the amount of hedging volume. Perhaps surprisingly, (iii) noise trade may be Pareto‐improving. Noise trade may be viewed as a public good. Results i and ii are compatible with observed high levels of turnover in securities markets. Result iii illustrates some of the possible subtcties of the welfare economics of financial markets. In our model, all agents are rational: some trade for hedging reasons, investors optimally contract with portfolio managers who may have stock‐picking abilities, and portfolio managers trade optimally given the incentives provided by this contract.