Optimal Exercise Prices for Executive Stock Options
解释了为何高管股票期权几乎都平价发行，并提出了一个替代Black-Scholes模型的实用方法，用于评估期权价值和激励效果，对行权价政策、指数期权等有启示。
Although exercise prices for executive stock options can be set either below or above the grant-date market price, in practice virtually all options are granted at the money. We offer an economic rationale for this apparent puzzle, by showing that pay-to-performance incentives for risk-averse undiversified executives are typically maximized by setting exercise prices at (or near) the grant-date market price. We provide an operationally useful alternative to Black-Scholes (1973) for the purpose of both valuing executive stock options and measuring the incentives created by options. Our framework has implications not only for exercise-price policies, but also for indexed options, option repricings, exchanges of cash for stock-based compensation, and the design of bonus plans.