 Say that an individual is risk-averse in money (or any numerical good) if she prefers the consequences of a gamble to be less “spread out”; this concept is made precise by Rothschild and Stiglitz’s idea of dispreferring mean-preserving spreads (1972). As a special case of this, a person who is risk-averse in money will prefer \(\$x\) to any gamble whose mean monetary value is \(\$x.\) If an EU maximizer is risk-averse in money, then her utility function will be concave (it diminishes marginally, i.e., each additional dollar adds less utility than the previous dollar); if an EU maximizer is risk-seeking in money, then her utility function will be convex (Rothschild &amp; Stiglitz 1972). Therefore, EU theory equates risk-aversion with having a diminishing marginal utility function.