Consistent with predictions from a stylized Bayesian learning model stock return volatility declines with CEO tenure in a convex manner, even for CEOs whose appointments occur for exogenous reasons. The decline is faster when there is higher uncertainty about the CEO's ability when there is more transparency about the firm's prospects, and when CEO ability is more important in value creation. We quantify the importance of uncertainty about CEO ability relative to the firm's fundamental cash flow uncertainty in contributing to stock return volatility, highlighting the importance of management in creating value.

Consistent with predictions from a stylized Bayesian learning model stock return volatility declines with CEO tenure in a convex manner, even for CEOs whose appointments occur for exogenous reasons. The decline is faster when there is higher uncertainty about the CEO's ability when there is more transparency about the firm's prospects, and when CEO ability is more important in value creation. We quantify the importance of uncertainty about CEO ability relative to the firm's fundamental cash flow uncertainty in contributing to stock return volatility, highlighting the importance of management in creating value.

Managers often claim that target firms are financially constrained prior to being acquired and that these constraints are eased following the acquisition. Using a large sample of European acquisitions, we document that the level of cash that target firms hold, the sensitivity of cash to cash flow, and the sensitivity of investment to cash flow all decline, while investment increases following the acquisition. These effects are stronger in deals that are more likely to be associated with financing improvements. Our findings suggest that acquisitions relieve financial frictions in target firms, especially when the target firm is relatively small.