Product Market Competition, Insider Trading, and Stock Market Efficiency
研究了产品市场竞争如何影响企业股票市场行为，发现垄断势力使企业将冲击转嫁给客户，稳定利润，从而促进股票交易、加速信息融入股价并改善资本配置。
ABSTRACT How does competition in firms' product markets influence their behavior in equity markets? Do product market imperfections spread to equity markets? We examine these questions in a noisy rational expectations model in which firms operate under monopolistic competition while their shares trade in perfectly competitive markets. Firms use their monopoly power to pass on shocks to customers, thereby insulating their profits. This encourages stock trading, expedites the capitalization of private information into stock prices and improves the allocation of capital. Several implications are derived and tested.