From a new working paper by David Yermack, an economist at NYU/Stern, called "Tailspotting: How Disclosure, Stock Prices and Volatility Change When CEOs Fly to Their Vacation Homes" (abstract; older version in PDF):
This paper shows close connections between CEOs' vacation schedules and corporate news disclosures. I identify vacations by merging corporate jet flight histories with real estate records of CEOs' property owned near leisure destinations. Companies disclose favorable news just before CEOs leave for vacation and delay subsequent announcements until CEOs return, releasing news at an unusually high rate on the CEO's first day back. When CEOs are away, companies announce less news than usual and stock prices exhibit sharply lower volatility. Volatility increases immediately when CEOs return to work.