The need to predict the future, as exciting as it sounds, crops up in corporate life in terribly mundane ways. Case in point: large video-game companies need to know where to put their marketing dollars many months before they complete their games. Inevitably, some games will be stinkers, hardly worth the investment of an ad campaign. But how do you know which ones?

Here's how one very large video-game company used to guess the answer: its marketing people would predict the score their games in progress would garner on the website Metacritic, which aggregates game reviews. But why would the marketing people know more than the game's developers?