that wage earnings in the gang were somewhat higher than legal market alternatives, but did not offset the increased risks associated with selling drugs. They suggested that the prospect of high future earnings is the primary economic motivation for being in a gang. Link between drunk driving and accident rates Levitt and Porter (2001) found that drivers with alcohol in their blood are seven times more likely to cause a fatal crash than sober drivers (those above the legal limit are 13 times more likely than sober drivers). They estimate that the externality per mile driven by a drunk driver is at least thirty cents, which implies that the proper fine to internalize this cost is roughly $8,000. Cheating in sumo wrestling and by teachers in schools Duggan and Levitt (2002) showed how non-linear payoff schemes establish incentives for corruption and the authors used the non-linearity to provide substantial statistical evidence that cheating is taking place in Japanese sumo wrestling. Brian Jacob and Levitt (2003) developed an algorithm to detect teachers who cheat for their students on standardized tests. They found that the observed frequency of cheating appears to respond strongly to relatively minor changes in incentives. Politics Levitt's work on politics includes papers on the effects of campaign spending, on the median voter theorem, and on the effects of federal spending. Levitt's 1994 paper on campaign spending employs a unique identification strategy to control for the quality of each candidate (which in previous work had led to an overstatement of the true effect). It concludes that campaign spending has a very small impact on election outcomes, regardless of who does the spending. On the subject of federal spending and elections, previous empirical studies were not able to establish that members of Congress are rewarded by the electorate for bringing federal dollars to their district because of omitted variables bias. Levitt and Snyder (1997) employ an instrument which circumvents this problem and finds evidence that federal spending benefits congressional incumbents; they find that an additional $100 per capita spending is worth as much as 2 percent of the popular vote. The 1996 paper on the median voter theorem develops a methodology for consistently estimating the relative weights in a senator's utility function and casts doubt on the median voter theorem, finding that the senator's own ideology is the primary determinant of roll-call voting patterns. Other studies Showed that the consumer