We characterize the conditions under which efficient portfolios put small weights on individual assets. These conditions bound mean returns with measures of average absolute covariability between assets. The bounds clarify the relationship between linear asset pricing models and well‐diversified efficient portfolios. We argue that the extreme weightings in sample efficient portfolios are due to the dominance of a single factor in equity returns. This makes it easy to diversify on subsets to reduce residual risk, while weighting the subsets to reduce factor risk simultaneously. The latter involves taking extreme positions. This behavior seems unlikely to be attributable to sampling error.

We provide empirical restrictions of a model of optimal order submissions in a limit order market. A trader's optimal order submission depends on the trader's valuation for the asset and the trade-offs between order prices, execution probabilities and picking off risks. The optimal order submission strategy is a monotone function of a trader's valuation for the asset. We test the monotonicity restriction in a sample of order submissions and their realized outcomes from the Stockholm Stock Exchange. We do not reject the monotonicity restriction for buy orders or sell orders considered separately, but reject the monotonicity restriction for buy and sell orders considered jointly.

Municipal bonds trade in decentralized broker-dealer markets, and are underpriced when issued, but unlike equities the average price rises slowly over several days. Newly issued municipal bonds have high levels of price dispersion and the average price rises because the mix of trade sizes changes over time. While large trades occur close to the reoffering price, small trades occur between the reoffering price to as much as 5% above the reoffering price. Using a mixed-distribution model we quantify the losses uninformed traders or issuers give up to broker-dealers.

[Municipal bonds trade in opaque, decentralized broker-dealer markets in which price information is costly to gather. We analyze a database of trades between broker-dealers and customers in municipal bonds. These data were only released to the public with a lag; the market was opaque. Dealers earn lower average markups on larger trades, even though dealers bear a higher risk of losses with larger trades. We estimate a bargaining model and compute measures of dealer's bargaining power. Dealers exercise substantial market power. Our measures of market power decrease in trade size and increase in the complexity of the trade for the dealer.]

Municipal bonds trade in opaque, decentralized broker-dealer markets in which price information is costly to gather. We analyze a database of trades between broker-dealers and customers in municipal bonds. These data were only released to the public with a lag; the market was opaque. Dealers earn lower average markups on larger trades, even though dealers bear a higher risk of losses with larger trades. We estimate a bargaining model and compute measures of dealer?s bargaining power. Dealers exercise substantial market power. Our measures of market power decrease in trade size and increase in the complexity of the trade for the dealer.

We study a model where firms may possess free cash flow and takeovers may be disruptive. We show that the possibility of a takeover, combined with defensive mechanisms and the ability to pay greenmail, can solve the free cash flow problem in an efficient way. The payment of greenmail reveals information that generates a stock price decline that exceeds the value of the greenmail payment, even though the payment of greenmail is value maximizing. Optimal defensive measures limit takeover attempts if the target stock price is too low. We also provide cross‐sectional implications of the analysis.

The authors study a model where firms may possess free cash flow and takeovers may be disruptive. They show that the possibility of a takeover, combined with defensive mechanisms and the ability to pay greenmail, can solve the free cash flow problem in an efficient way. The payment of greenmail reveals information that generates a stock price decline that exceeds the value of the greenmail payment, even though the payment of greenmail is value maximizing. Optimal defensive measures limit takeover attempts if the target stock price is too low. The authors also provide cross-sectional implications of the analysis.

We study a model where firms may possess free cash flow and takeovers may be disruptive. We show that the possibility of a takeover, combined with defensive mechanisms and the ability to pay greenmail, can solve the free cash flow problem in an efficient way. The payment of greenmail reveals information that generates a stock price decline that exceeds the value of the greenmail payment, even though the payment of greenmail is value maximizing. Optimal defensive measures limit takeover attempts if the target stock price is too low. We also provide cross-sectional implications of the analysis.

Elementary portfolio theory implies that environmentalists optimally hold more shares of polluting firms than non-environmentalists, and that polluting firms attract more investment capital than otherwise identical non-polluting firms through a hedging channel. Pigouvian taxation can reverse the aggregate investment results, but environmentalists still overweight polluters. We introduce countervailing motives for environmentalists to underweight polluters, comparing the implications when environmentalists coordinate to internalize pollution, or have nonpecuniary disutility from holding polluter stock. With nonpecuniary disutility, introducing a green derivative may dramatically alter who invests most in polluters, but has no impact on aggregate pollution.

We examine the effect of segmented commodity markets on the relation between forward and future spot exchange rates in a dynamic economy. We calculate the slope coefficient in our theoretical economy from regressing exchange rate changes on forward premia. With reasonable parameter values, the slope coefficient is less than unity. However, even for extreme parameters the slope is not less than zero, as found in the data. A negative slope coefficient in a nominal version of the model requires the covariance between monetary shocks and relative output shocks to be significantly negative, in contrast to the covariance in the data.