Using a very large data set with more than 9,700 stocks listed on NYSE, AMEX and NASDAQ, we analyze overnight price jumps and report short-term investor overreaction to information shocks and document return reversal and predictability up to five days. For negative and positive overnight jumps,...

Modern financial markets offer the real world's best approximation to the idealized price auction market envisioned in economic theory. Nevertheless, as the increasingly exquisite and detailed financial data demonstrate, financial markets often fail to behave as they should if trading were truly...