We’re talking decision trees, which have been around since the early 1960s. They’re a useful tool in which the decision maker outlines the choices and possible outcomes, along with probability estimates for each outcome. For example, you’re planning a weekend outdoor sports tournament, with ticket sales, concessions, and both players and spectators travel- ing many miles to attend. But there’s a hurricane forming off the coast, with the National Weather Service assigning a 30% probability of its passing through the area at the time of the tournament. If it hits, the event is a washout, and you incur a loss from wasted advertising expenses, ticket refunds, and the like. If it misses, the weekend is a huge success. Do you postpone/ cancel, or go ahead as originally planned?