Risk Averse or Risk Lovers

What does it mean to say that a person is risk averse? 

Why are some people likely to be risk averse while others are risk lovers?

ANSWER

A risk-averse person has a diminishing marginal utility of income and prefers a certain income to a gamble with the same expected income. A risk lover has an increasing marginal utility of income and prefers an uncertain income to a certain income when the expected value of the uncertain income equals the certain income. To some extent, a person’s risk preferences are like preferences for different vegetables. They may be inborn or learned from parents or others, and we cannot easily say why some people are risk averse while others like taking risks. But there are some economic factors that can affect risk preferences. For example, a wealthy person is more likely to take risks than a moderately well-off person, because the wealthy person can better handle losses. Also, people are more likely to take risks when the stakes are low (like office pools around NCAA basketball time) than when stakes are high (like losing a house to fire).