the deterrent effect of capital punishment evidence from a judicial experiment i introduction the contemporary debate over capital punishment involves a number of important arguments based on either moral principles or social welfare considerations the primary social welfare issue viewed as the most important single consideration for both sides in the death penalty controversy is whether capital punishment deters capital crimes see for example zimring and hawkins 1986 this issue is also of great interest to several states that are currently considering a change in their death penalty laws 1 psychologists and criminologists studied the death penalty initially and reported no deterrent effect see for example sellin 1959 and eysenck 1970 economists joined the debate later with ehrlich s 1975 and 1977 studies that report a significant deterrent effect applying regression analysis to u s aggregate data for 1933 69 and state level data for 1940 and 1950 ensuing studies use either ehrlich s data with different regression specifications different regressors functional form or endogenous variables or postmoratorium data with a variant of ehrlich s regression model results range from a substantial deterrent effect to no effect or a small adverse effect 2 this study uses a new approach to advance the deterrence literature we exploit an important characteristic that other studies have not considered the experimental nature of the moratorium that the supreme court imposed on executions during the 1970s the moratorium can be viewed as an exogenously imposed judicial experiment the experiment s effect on murder rates provides evidence about the deterrent effect of capital punishment we compare the murder rate for each state immediately before and after it suspended or reinstated the death penalty many factors that affect crime for example law enforcement judicial demographic and economic variables change only slightly over a short period of time therefore changes in a state s murder rate quickly following a change in its death penalty law can be attributed to the legal change also there are considerable cross state variations in the timing and duration of the moratorium that began and ended in different years in different states ranging from four to thirty years see tables 1 and 2 3 these variations can strengthen our comparison based inference because observing similar changes in murder rates immediately after the same legal change in different years and in various states provides compelling evidence of the moratorium s effect on murder moreover our analysis benefits from the experiences of the states that suspended and reinstated their death penalty statutes several times 4 for states that experience similar murder rate changes after suspensions or reinstatements in different crime economic and demographic environments the contribution of the legal change to murder is paramount we supplement the before and after comparisons with time series and panel data regression analyses unlike most existing studies we use both pre and postmoratorium data the regressions disentangle the effect of having death penalty laws on murder from the effect of actual executions on murder basing our inference on two different approaches allows us to corroborate our findings and also detract from the modeling concerns voiced at previous studies that use only regression analysis we also apply a battery of tests to examine the robustness of the findings these include regression sensitivity checks with 89 additional regression equations that differ from our base models in regressors functional form data and estimation method in addition we test whether the moratorium has an effect on property crimes that are not punishable by death if the relationship between the moratorium and these crimes is similar to the relationship between the moratorium and murder then we should suspect that murder rate changes are the result of broader trends in criminal behavior affecting all crimes

residential energy demand in oecd countries and the role of irreversible efficiency improvements abstract after undergoing substantial changes during a period of high energy prices household energy demand did not rebound in times of declining energy prices as might have been expected hence other factors such as irreversible improvements in technical efficiency must be understood in order to describe both past and future household energy demand in this paper we consider irreversible efficiency improvements as a major reason for the moderate growth in energy demand after the plummeting of the oil price in 1985 we test different econometric models to take into account efficiency indicators the major conclusions of our investigation are i price elasticities are different for rising and falling prices for the latter they are close to zero implying a low rebound effect in the residential sector ii technical efficiency is an important parameter for describing and forecasting energy demand and iii income elasticities turn out to be higher once we incorporate indicators of technological efficiency in the process of estimating energy demand

crime rates and local labor market opportunities in the united states 1979 1997 the labor market prospects of young unskilled men fell dramatically in the 1980s and improved in the 1990s crime rates show a reverse pattern increasing during the 1980s and falling in the 1990s because young unskilled men commit most crime this paper seeks to establish a causal relationship between the two trends previous work on the relationship between labor markets and crime focused mainly on the relationship between the unemployment rate and crime and found inconclusive results in contrast this paper examines the impact of both wages and unemployment on crime and uses instrumental variables to establish causality we conclude that both wages and unemployment are significantly related to crime but that wages played a larger role in the crime trends over the last few decades these results are robust to the inclusion of deterrence variables controls for simultaneity and controlling for individual and family characteristics

how fragile are fragile inferences a re evaluation of the deterrent effect of capital punishment extreme bounds analysis attempts to measure the effects of the uncertainty in the specification of the explanatory variables in a regression model on the estimated coefficients of interest standard errors for the stochastic extreme bounds are computed using the bootstrap technique state by state cross section data are used to study the deterrent effect of capital punishment in the united states in 1950 the bootstrap standard errors are sufficiently large for some bounds to suggest caution in the interpretation of the empirical results regarding the fragility of inferences for the deterrent effect of capital punishment copyright 1989 by mit press

dead man walking an empirical reassessment of the deterrent effect of capital punishment using the bounds testing approach to cointegration this paper empirically estimates a murder supply equation for the united states from 1965 to 2001 within a cointegration and error correction framework our findings suggest that any support for the deterrence hypothesis is sensitive to the inclusion of variables for the effects of guns and other crimes in the long run we find that real income and the conditional probability of receiving the death sentence are the main factors explaining variations in the homicide rate in the short run the aggravated assault rate and robbery rate are the most important determinants of the homicide rate

the retirement wealth of the baby boom generation abstract the paper compares the well being of the baby boom generation ages 40 55 in 2001 with the same age group in 1983 i find little evidence that their relative position deteriorated over the period by some indicators this generation has seen an improvement in terms of income the 40 55 age group was at about the same relative position in 2001 as in 1983 in terms of conventional wealth there was some slippage over the period in terms of mean augmented wealth net worth plus pension and social security wealth their relative position improved somewhat but in terms of median augmented wealth there was again some slippage

cohort size and the earnings growth of young workers this study used data from the 1968 75 current population surveys cps and the national longitudinal survey of young men nls to examine the effect of cohort size on earnings profiles in the us the elasticity of earnings growth with respect to cohort size was negative in each of the regressions analyzed indicating flatter earnings profiles and slower earnings growth for large cohorts a larger proportion of workers in large cohorts appear to choose occupations with less training content and flatter earnings profiles than workers in small cohorts in addition workers in large cohorts may find it advantageous to reduce their investments in training the negative effect of cohort size generally carried over to other schooling and gender groups only for the 2 lowest male schooling groups in the cps samples were the cohort size elasticities positive the cohort size elasticity displayed a larger negative effect for college graduates than for high school graduates or those with some college education the predicted earnings growth of college graduates is 11 6 less than that of high school graduates using the male cps parameter estimates 25 3 less with the female cps estimates and 6 less with the nls estimates these estimates are consistent with freemans finding that the longitudinal earnings profiles of college graduates have flattened relative to those of high school graduates in recent years since the initial earnings depression caused by cohort size widens with age as larger cohorts move along flatter earnings profiles the baby boom cohorts earnings levels may remain depressed throughout their careers on the other hand the smaller cohorts entering the labor market during the 1980s are likely to experience more favorable labor market conditions and faster earnings growth

more efficient household electricity use since 1973 the efficiency of most energy uses in homes has improved throughout the oecd 1 this means that to provide a given amount of energy service for example heating cooling locomotion or mechanical force less energy is required today than was needed in the past these improvements have been gained through the introduction of new appliances and for space heating and cooling new homes with more efficient building shells and the retrofitting of the existing building stock in this report we analyse some of the past changes in the efficiency of household appliance electricity use and discuss prospects for and barriers to further increases in the future

the credibility revolution in empirical economics how better research design is taking the con out of econometrics since edward leamer s memorable 1983 paper let s take the con out of econometrics empirical microeconomics has experienced a credibility revolution while leamer s suggested remedy sensitivity analysis has played a role in this we argue that the primary engine driving improvement has been a focus on the quality of empirical research designs the advantages of a good research design are perhaps most easily apparent in research using random assignment we begin with an overview of leamer s 1983 critique and his proposed remedies we then turn to the key factors we see contributing to improved empirical work including the availability of more and better data along with advances in theoretical econometric understanding but especially the fact that research design has moved front and center in much of empirical micro we offer a brief digression into macroeconomics and industrial organization where progress by our lights is less dramatic although there is work in both fields that we find encouraging finally we discuss the view that the design pendulum has swung too far critics of design driven studies argue that in pursuit of clean and credible research designs researchers seek good answers instead of good questions we briefly respond to this concern which worries us little

the effect of prison population size on crime rates evidence from prison overcrowding litigation simultaneity between prisoner populations and crime rates makes it difficult to isolate the causal effect of changes in prison populations on crime to break that simultaneity this paper uses prison overcrowding litigation in a state as an instrument for changes in the prison population the resulting elasticities are two to three times greater than those of previous studies a one prisoner reduction is associated with an increase of fifteen index i crimes per year while calculations of the costs of crime are inherently uncertain it appears that the social benefits associated with crime reduction equal or exceed the social costs of incarceration for the marginal prisoner

the economic epidemiology of crime economic analysis of infectious diseases emphasizes the self correcting character of epidemics as rising risk of infection causes potential victims to take self protective measures we apply the analysis to crime showing how rational potential victims of crime will take increased self protective measures in response to rising crime rates causing those rates to moderate victim responses to crime can offset public expenditures on crime control this implies that there may be a natural rate of crime that is difficult for the public sector to affect we show that victim responses to crime can impart a cyclical pattern to crime rates and discuss the implications of our analysis for gun control and present empirical evidence concerning the responsiveness of self protective measures to crime rates and the cyclical pattern of those rates

empirical age earnings profiles the human capital earnings function in which earnings are expressed as a quadratic in potential experience is probably the most widely accepted empirical specification in economics in spite of its widespread acceptance the human capital earnings function provides a very poor approximation of the true empirical relationship between earnings and experience the standard formulation understates early career earnings growth by about 30 50 and overstates midcareer growth by 20 50 however simple alternative specifications that fit the data are available

does the right to carry concealed handguns deter countable crimes only a count analysis can say abstract an analysis of the effects of right to carry laws on crime requires particular distributional and structural considerations first because of the count nature of crime data and the low number of expected instances per observation in the most appropriate data least squares methods yield unreliable estimates second use of a single dummy variable as a measure of the nationwide effect of right to carry laws is likely to introduce geographical and intertemporal aggregation biases into the analysis in this paper we use a generalized poisson process to examine the geographical and dynamic effects of right to carry laws on reported homicides rapes and robberies we find that the effects of such laws vary across crime categories u s states and time and that such laws appear to have statistically significant deterrent effects on the numbers of reported murders rapes and robberies

sensitivity analyses of the deterrence hypothesis let s keep the econ in econometrics abstract leamer and mcmanus applied extreme bound analysis eba in an empirical study of the deterrent effects of capital punishment and other penalties their analysis has questioned the validity of the deterrence hypothesis the thrust of our paper is twofold first by applying eba to well known econometric models of demand production and human capital investment our analysis exposes and illustrates the inherent flaws of eba as a method of deriving valid inferences about model specification second since the analysis shows leamer and mcmanus s inferences about deterrence to be based on a flawed methodology we offer an alternative theory based sensitivity analysis of estimated deterrent effects using similar data our analysis supports the deterrence hypothesis more generally it emphasizes the indispensable role of theory in guiding sensitivity analyses of model specification

a framework for analyzing the impact of cohort size on education and labor earning the paper analyzes three models of labor demand solving for the change in wages of a given labor group due to a change in the size of a birth cohort when the production function includes age schooling groups as separate factors an increase in the size of one birth cohort changes the size of several labor market groups also in this case the demand effect of changing factor size is joined by a supply effect of changing schooling proportions ignoring the supply effect may cause us to overestimate the effect of a large birth cohort on wages of young skilled workers

norwegian residential electricity demand a microeconomic assessment of the growth from 1976 to 1993 abstract the norwegian residential electricity consumption increased by an average of 3 annually during the period 1976 1993 political signals indicate that the growth in norwegian residential energy consumption should be reduced and that it may be necessary to increase energy taxes based on data for the sample of households from the annual consumer expenditure survey we study factors that are of importance explaining the growth in norwegian residential electricity demand during this period nearly half of the growth is due to an increase in the number of households while the rest reflects an increase in average consumption per household the increase in average consumption per household is due to an increasing number of households possessing electric household appliances such as dryers and dishwashers an increase in real disposable household income and in the floor space of dwellings

environmental regulation of households an empirical review of economic and psychological factors abstract the literature on sustainable consumption and environmental regulation of household behavior is dominated by conceptual and normative approaches as a result many suggestions lack a firm empirical basis to overcome this deficiency econometric studies in three areas of environmentally relevant activities of households are reviewed residential use of energy generation of solid waste and recycling and residential use of water next to price and income elasticities attention is devoted to individual socio economic features and psychological factors such as attitudes knowledge perceptions and values potential psychological determinants and related insights are further examined by discussing a range of representative and illustrative statistical psychological studies of environmental behavior one important general finding is that there are very few empirical studies that systematically combine socio economic and psychological determinants a range of insights for environmental policy is derived and research recommendations are offered

model averaging in economics an overview standard practice in empirical research is based on two steps first researchers select a model from the space of all possible models second they proceed as if the selected model had generated the data therefore uncertainty in the model selection step is typically ignored alternatively model averaging accounts for this model uncertainty in this paper i review the literature on model averaging with special emphasis on its applications to economics finally as an empirical illustration i consider model averaging to examine the deterrent effect of capital punishment across states in the usa

impacts on electricity consumption of household appliances in austria a comparison of time series and cross section analyses abstract in this paper electricity consumption of household appliances in austria is investigated to extract the impact of various parameters two different approaches are compared a time series from 1960 1995 and a cross section analysis these analyses lead to the following results the price elasticity is virtually zero the income elasticity is high but decreasing the major conclusion is that with respect to appliance electricity consumption the rebound effect is low and hence efficiency is the most important slower of electricity consumption therefore standards labelling and other instruments focusing on an increase of efficiency are the most important tools of energy policy for this end use

estimating the economic model of crime with panel data previous attempts at estimating the economic model of crime with aggregate data relied heavily on cross section econometric techniques and therefore do not control for unobserved heterogeneity this is even true of studies that estimated simultaneous equations models using a new panel data set of north carolina counties the authors exploit both single and simultaneous equations panel data estimators to address two sources of endogeneity unobserved heterogeneity and conventional simultaneity their results suggest that both labor market and criminal justice strategies are important in deterring crime but that the effectiveness of law enforcement incentives has been greatly overstated copyright 1994 by mit press

marginal deterrence at work abstract the marginal deterrence principle of law enforcement implies that penalties must be scaled according to the severity of crimes in order to deter individuals from committing more severe offenses in this paper we test whether the us legal system is consistent with the rational economic model of marginal deterrence to this purpose we use novel and unique data on sentence length for a large sample of inmates in us correctional facilities combined with an official ranking of crimes by severity and with proxies for the maximum possible punishment and for the cost of monitoring criminals specifically the cost of policing in each us state over a period spanning up to 50 years we find that sentences are on average longer in states where maximum punishment is higher and monitoring cost is lower we document that these relations are systematically stronger in states where the private benefits from crime are more heterogeneous finally we show that sanctions increase relatively faster with the severity of crimes in states with higher maximum punishment and lower monitoring cost overall these results point to the rational economic model of marginal deterrence as providing a reasonable description of the actual enforcement policies chosen by regulators

predicted future earnings and choice of college major using data from the national longitudinal survey of young men the author of this paper examines the relationship between predicted future earnings for five broad fields of study and college students choice of major conditional logit models of major choice that incorporate alternative predicted earnings variables are specified and estimated the results indicate that holding family background characteristics constant individuals are likely to choose majors offering greater streams of future earnings rather than as some have argued majors with higher beginning earnings at the time of the choice it is also found that earnings profiles corrected for self selection bias have flattened for more recent graduates in business liberal arts and education the life cycle earnings in these disciplines appear to be more severely depressed than those in science and engineering

estimations of the economic model of crime using aggregate and individual level data much has happened in the economics of crime since becker s 1 seminal paper of two decades ago the theory has been refined by among others ehrlich 10 11 12 block and lind 4 5 block and heinke 3 and schmidt and witte 30 attempts to test the model empirically began immediately the most cited including ehrlich 10 11 12 sjoquist 31 carr hill and stern 7 phillips and votey 26 witte 38 and myers 22 23 interest continues with recent work including layson 19 sandelin and skogh 29 ehrlich and brower 13 cover and thistle 9 viscusi 36 and tauchen witte and griesinger 33 there has been some controversy however concerning the type of data more suitable to the estimation of the economic model of crime most of the work has used aggregate data in which the unit of observation is a political jurisdiction but the use of aggregate data has been sharply criticized the alternative is individual data few attempts have been made to use individual data probably because an ideally constructed data set representative of a general population would be far too costly for most research budgets most of the studies that have been done have used data on releasees from prison or other criminal justice programs they are in effect recidivism studies based on the economic model of crime

time series homicide and the deterrent effect of capital punishment erlich 5 6 presents regression results showing that the u s time series data supports the deterrent effect of capital punishment the deterrence hypothesis other researchers 9 10 16 criticize erlich s findings on a number of grounds including the possibility of simultaneity bias and the sensitivity of the results to the choice of sample period control variables and functional form layson 11 extends erlich s u s sample to the 1936 1977 period and taking account of these criticisms concludes that the u s time series evidence provides robust support for the deterrence hypothesis this paper contributes to the debate on the deterrence hypothesis by analyzing the time series properties of the homicide rate the u s homicide rate is a nonstationary time series it is well known that the use of nonstationary series in regression analysis leads to inconsistent coefficient estimators biases estimators of coefficient standard errors toward zero and invalidates standard statistical inference procedures 2 8 13 14 15 17 18 nonstationarity may be due to a linear trend trend nonstationarity or may be a property of the underlying stochastic process difference nonstationarity if the time series is difference nonstationary then use of a linear trend does not correct these problems and may be misleading 13 14 15 we explicitly test for the source of the nonstationarity of the homicide rate difference or trend nonstationarity using the tests recently developed by dickey and fuller 3 4 7 we find that the homicide rate is difference nonstationary this implies that the data must be first differenced to achieve stationarity and that use of a linear trend as in 5 6 9 10 11 16 is inappropriate the regression results obtained using the first differenced stationary data do not provide robust support for a deterrence effect of capital punishment

execution and deterrence a quasi controlled group experiment using portfolio analysis in a type of controlled group experiment this study develops an empirical model of homicide changes in texas over a period of a normal number of executions the empirically derived model then estimates the changes in the number of homicides in texas 1 over a period of near zero executions and 2 over an immediate subsequent period of double the normal number of executions the actual changes in texas homicides over the first period is less than estimated by the model and greater or no different than estimated by the model in the second period because changes in the number of homicides in texas and throughout the united states were negative over both periods these empirical results are consistent with the deterrence hypothesis that is there were a greater than predicted number of homicides in the first period and fewer than predicted number in the second period

the impact of legalized abortion on crime we offer evidence that legalized abortion has contributed significantly to recent crime reductions crime began to fall roughly eighteen years after abortion legalization the five states that allowed abortion in 1970 experienced declines earlier than the rest of the nation which legalized in 1973 with roe v wade states with high abortion rates in the 1970s and 1980s experienced greater crime reductions in the 1990s in high abortion states only arrests of those born after abortion legalization fall relative to low abortion states legalized abortion appears to account for as much as 50 percent of the recent drop in crime

from the econometrics of capital punishment to the capital punishment of econometrics on the use and abuse of sensitivity analysis the academic debate over the deterrent effect of capital punishment has intensified again with a major policy outcome at stake about two dozen empirical studies have recently emerged that explore the issue donohue and wolfers 2005 claim to have examined the recent studies and shown the evidence not to be robust to specification changes we argue that the narrow scope of their study does not warrant this claim moreover focusing on our two studies that they have examined we show the deterrence findings to be robust while their work has serious flaws and their reporting appears to be selective the selectivity is biased towards showing no deterrence

criminal behaviour and youth in the labour market the case of the pernicious minimum wage this paper empirically tests the relationship between variations in uniform crime reports ucr index crime rates for teenagers 16 19 years of age with changes in the real minimum wage adjusted for industry coverage in the united states for the period 1960 1987 the analysis reveals that there exists a positive relationship between changes in the real minimum wage and teenage criminal homicide forcible rape and motor vehicle theft crime rates these findings are consistent with the empirical evidence concerning the impacts of the minimum wage on youth labour market opportunities and also with the theoretical ad empirical evidence regarding the incidence of criminal activity made as an occupational choice decision formulated under risk and uncertainty however the results indicate no impact of the minimum wage on the other teenage ucr index crime rates as found by hashimoto 1987 the evidence also suggests that variations in real criminal justice expenditures per capita reduce teenage propety crime ra