Additional sensitivity tests Clause Samples

Additional sensitivity tests. In additional tests (untabulated), we include an outside blockholder dummy as a control variable, because an outside blockholder has increased supervisory incentives due to his large stake in the firm. An outside blockholder is a shareholder who has at least 5% ownership in the firm and is not an officer, a director, an affiliated entity, or otherwise employed by the firm. The board-independence coefficient estimates are equal in magnitude to those obtained in our original regressions, but, because the blockholder database ends in 2001, our sample size sharply decreases to 350 observations with the inclusion of this variable, thereby increasing the standard errors of the board- independence coefficient estimates (resulting in t-statistics of -1.86 and -1.65, respectively, when using the Salary + Bonus and Total Compensation measures). As always, we use White standard errors adjusted for clustering by firm. Whether the outside blockholder dummy is included or not, compensation regressions within this reduced sample (of 350 observations) yield very similar board-independence coefficient estimates and standard errors. Furthermore, our results continue to hold under the following alternative specifications of our empirical tests (untabulated): calculating total compensation using the Black-Scholes value of options instead of converting them into their stock equivalents; estimating quantile regressions to reduce the influence of potential outliers; including the CEO’s first-year level of compensation as an additional control for CEO quality; adding squared values of our independent variables to capture possible nonlinearities; adjusting variables by the industry median (as opposed to adjusting by the mean); including an Other Provisions index in place of the Democracy and Dictatorship dummies (the Other Provisions index is equal to the GIM index minus one if the firm has a classified-board provision, and minus zero otherwise); and including the Bebchuk, ▇▇▇▇▇, and ▇▇▇▇▇▇▇ (2004) index in place of the Classified-Board, Democracy, and Dictatorship dummies (the BCF index accrues one point for each of the following provisions: classified board, poison pill, golden parachute, limits to bylaw amendments, supermajority requirements for charter amendments, and supermajority requirements for mergers).