New Releases by Steven D. Levitt

Over the last two decades the punitiveness of the juvenile justice system has declined" substantially relative to the adult courts. During that same time period juvenile violent crime" rates have grown almost twice as quickly as adult crime rates. This paper examines the degree to" which those two empirical observations are related, finding that changes in relative punishments" can account for 60 percent of the differential growth rates in juvenile and adult violent crime" between 1978 and 1993. Juvenile offenders appear to be at least as responsive to criminal" sanctions as adults. Moreover, sharp changes in criminal involvement with the transition from" the juvenile to the adult court suggest that deterrence, rather than simply incapacitation important role. There does not, however, appear to be a strong relationship between the" punitiveness of the juvenile justice system that a cohort faces and the extent of criminal" involvement for that cohort later in life.

This paper demonstrates that rising crime rates in cities are correlated with city depopulation. Instrumental variables estimates, using measures of the certainty and severity of a state?s criminal justice system as instruments for city crime rates, imply that the direction of causality runs from crime to urban flight. Using annual city-level panel data, our estimates suggest that each additional reported crime is associated with a one person decline in city residents. There is some evidence that increases in suburban crime tend to keep people in cities, although the magnitude of this effect is small. Analysis of individual-level data from the 1980 census confirms the city-level results and demonstrates that almost all of the crime-related population decline is attributable to increased outmigration rather than a decrease in new arrivals to a city. Those households that leave the city because of crime are much more likely to remain within the SMSA than those leaving the city for other reasons. The migration decisions of high-income households and those with children are much more responsive to changes in crime than other households. Crime-related mobility imposes costs on those who choose to remain in the city through declining property values and a shrinking tax base.

Abstract: While it is widely believed by academics, politicians, and the popular press that incumbent congressmen are rewarded by the electorate for bringing federal dollars to their district, the empirical evidence supporting that claim is extremely weak. One explanation for the failure to uncover the expected relationship between federal spending and election outcomes is that incumbents who expect to have difficulty being reelected are likely to exert greater effort in obtaining federal outlays. Since it is generally impossible to adequately measure this effort, the estimated impact of spending is biased downward due to an omitted variable bias. We address this estimation problem using instrumental variables. For each House district, we use spending outside the district but inside the state containing the district, as an instrument for spending in the district. Federal spending is affected by a large number of actors (e.g. governors, senators, mayors, and other House members in the state delegation), leading to positive correlations in federal spending across the House districts within states. However, federal spending outside of a district is unlikely to be strongly correlated with the strength of that district''s electoral challenge. Thus, spending in other districts is a plausible instrument. In contrast to previous studies, we find strong evidence that non-transfer federal spending benefits congressional incumbents: an additional $100 per capita in such spending is worth as much as two percent of the popular vote. Additional transfer spending, on the other hand, does not appear to have any electoral effects.

Previous empirical studies have typically uncovered little evidence that police reduce crime. One problem with those studies is a failure to adequately deal with the simultaneity between police and crime: while police may or may not reduce crime, there is little doubt that expenditures on police forces are an increasing function of the crime rate. In this study, the timing of mayoral and gubernatorial elections is used to identify the effect of police on crime. This paper first demonstrates that increases in the size of police forces disproportionately occur in mayoral and gubernatorial election years, a relationship that had previously gone undocumented. After controlling for changes in government spending on other social programs, there is little reason to think that elections will be otherwise correlated with crime, making elections ideal instruments. Using a panel of large U.S. cities from 1970-1992, police are shown to reduce crime for six of the seven crime categories examined. Each additional police officer is estimated to eliminate eight to ten serious crimes. Existing estimates of the costs of crime suggest that the social benefit of reduced crime is approximately $100,000 per officer per year, implying that the current number of police is below the optimal level.

This paper tests several theories of the effects of congressional representation on state economic growth. States that were represented by very senior Democratic congressmen grew more quickly during the 1953-1990 period than states that were represented by more junior congressional delegations. We find some, but weaker, evidence that states with a high fraction of their delegation on particularly influential committees also exhibit above-average growth. We also test partisan models of distributive politics by studying the relationship between a state''s degree of political competition and its growth rate. Our findings support both nonpartisan and partisan models of congressional distributive politics. In spite of our findings with respect to economic growth, we can not detect any substantively important association between congressional delegation seniority, the degree of state political competition, and the geographic distribution of federal funds. The source of the growth relationships we identify therefore remains an open question.

Mọi người thường có xu hướng suy nghĩ và hành động theo đám đông, do vậy với những vấn đề quan trọng, chúng ta thường phải hỏi xin lời khuyên từ bạn bè, đồng nghiệp và người thân. Điều này đương nhiên không có hại trong ngắn hạn. Thế nhưng về lâu về dài việc hỏi ý kiến những người xung quanh sẽ dẫn bạn đi theo lối mòn đã mở sẵn, một tư duy kém đổi mới mà nếu tự suy ngẫm, theo một hướng khác hơn, đột phá hơn, lập dị hơn, bạn sẽ mở ra một hướng giải quyết thông minh hơn và khôn ngoan hơn. Trong cuốn sách Tư duy như một kẻ lập dị, Steve D.Levitt & Steph J.Dubner, đồng tác giả của hai cuốn sách Tư duy vô cùng lý thú pha chút hóm hỉnh Kinh Tế Học Hài Hước và Siêu Kinh Tế Học Hài Hước, sẽ một lần nữa dùng lối văn phong phá cách của mình để “mở khóa tư duy” của độc giả. Xin nhắc lại đây không phải là một cuốn sách Kỹ năng có tính hài hước, đơn giản chỉ là để giải trí, mà ngoài những yếu tố, những ví dụ vui nhộn, hai tác giả này còn muốn người đọc có được một thái độ tích cực hơn với những gì bất ngờ xảy đến, hãy luôn thoát khỏi lối mòn và trang bị cho mình những cách giải thích đơn giản nhất có thể. Tư Duy Như Một Kẻ Lập Dị xứng đáng là cuốn sách bán chạy viết về Tư duy cho tất cả những độc giả đam mê phát triển lối tư duy của mình.