We develop a return variance decomposition model to separate the role of different types of information and noise in stock price movements. We disentangle four components: market-wide information, private firm-specific information revealed through trading, firm-specific information revealed...

We examine the real effects of stock market efficiency by analyzing how noise in stock prices affects the efficiency of capital allocation. Using data from 42 countries and a long time-series, we find that the efficiency of capital allocation across firms (the sensitivity of corporate investment...