Individual Perceptions of the Criminal Justice System

This paper empirically examines perceptions of the criminal justice system held by young males using longitudinal survey data from the recent National Longitudinal Survey of Youth 1997 Cohort and the National Youth Survey. While beliefs about the probability of an arrest are positively correlated with local official arrest rates, they are largely idiosyncratic and unresponsive to information about the arrests of other random individuals and local neighborhood conditions. There is little support, therefore, for the `broken windows' theory of Wilson and Kelling (1982). Yet, perceptions do respond to changes in an individual's own criminal and arrest history. Young males who engage in crime but are not arrested revise their perceived probability of arrest downward, while those who are arrested revise their probability upwards. Beliefs respond similarly to changes in a sibling's criminal and arrest history. The perceived probability of arrest is then linked to subsequent criminal behavior. Cross-sectionally, youth with a lower perceived probability of arrest are significantly more likely to engage in crime during subsequent periods. Following an arrest, individuals commit less crime, consistent with deterrence theory and the fact that their perceived probability of arrest increases.

Nodal prices, capacity valuation and investments in natural gas markets - Overview and Analytical Framework

Especially in the short-term, prices in natural gas markets are not exclusively determined by overall supply and demand, but also by the availability of the transport infrastructure. If transportation capacity is scarce, prices may form in (local) residual markets and can differ regionally. If available, storages provide intertemporal arbitrage possibilities which also impact prices. Temporal and regional price differences, in turn, determine the value of storage and transport capacity if either one is scarce. This paper applies an analytical framework for a simple pipeline grid with a storage over two periods to illustrate the interdependencies between prices, scarce capacity and capacity value. The theoretically optimal transportation and storage tariffs are described analytically. The optimal pipeline investment size is shown to be related to marginal storage investment and a function of the discounted and aggregated cost of congestion over the lifetime's asset.Natural gas; Prices; Transport capacity; Storage; Investment

Individual Perceptions of the Criminal Justice System

crime, beliefs, deterrence, perceptions

The Changing Role of Family Income and Ability in Determining Educational Achievement

This paper uses data from the 1979 and 1997 National Longitudinal Survey of Youth cohorts (NLSY79 and NLSY97) to estimate changes in the effects of ability and family income on educational attainment for youth in their late teens during the early 1980s and early 2000s. Cognitive ability plays an important role in determining educational outcomes for both NLSY cohorts, while family income plays little role in determining high school completion in either cohort. Most interestingly, we document a dramatic increase in the effects of family income on college attendance (particularly among the least able) from the NLSY79 to the NLSY97. Family income has also become a much more important determinant of college `quality' and hours/weeks worked during the academic year (the latter among the most able) in the NLSY97. Family income has little effect on college delay in either sample. To interpret our empirical findings on college attendance, we develop an educational choice model that incorporates both borrowing constraints and a `consumption' value of schooling - two of the most commonly invoked explanations for a positive family income-schooling relationship. Without borrowing constraints, the model cannot explain the rising effects of family income on college attendance in response to the sharply rising costs and returns to college experienced from the early 1980s to early 2000s: the incentives created by a `consumption' value of schooling imply that income should have become less important over time (or even negatively related to attendance). Instead, the data are more broadly consistent with the hypothesis that more youth are borrowing constrained today than were in the early 1980s.

Civil Unrest in North Africa – Risks for Natural Gas Supply?

The uprising and military confrontation in Libya that began in February 2011 has led to disruptions of gas supplies to Europe. An analysis of how Europe has compensated for these missing gas volumes shows that this situation has not affected security of supply. However, this situation would change if the North African uprising were to spread to Algeria. Since Algeria is a much more important gas supplier to Europe than is Libya, more severe consequences would be likely. Applying a natural gas infrastructure model, we investigate the impact of supplier disruptions from both countries for a summer and winter period. Our analysis shows that disruptions in the low-demand summer months could be compensated for, mainly by LNG imports. An investigation of a similar situation at the beginning of the winter shows that security of supply would be severely compromised and that disruptions to Italian consumers would be unavoidable.Natural gas; security of supply; network modelling; North Africa

The Changing Role of Family Income and Ability in Determining Educational Achievement

This paper uses data from the 1979 and 1997 National Longitudinal Survey of Youth cohorts(NLSY79 and NLSY97) to estimate changes in the effects of ability and family income on educational attainment for youth in their late teens during the early 1980s and early 2000s. Cognitive ability plays an important role in determining educational outcomes for both NLSY cohorts, while family income plays little role in determining high school completion in either cohort. Most interestingly, we document a dramatic increase in the effects of family income on college attendance (particularly among the least able) from the NLSY79 to the NLSY97. Family income has also become a much more important determinant of college `quality' and hours/weeks worked during the academic year (the latter among the most able) in the NLSY97. Family income has little effect on college delay in either sample. To interpret our empirical findings on college attendance, we develop an educational choice model that incorporates both borrowing constraints and a `consumption' value of schooling – two of the most commonly invoked explanations for a positive family income - schooling relationship. Without borrowing constraints, the model cannot explain the rising effects of family income on college attendance in response to the sharply rising costs and returns to college experienced from the early 1980s to early 2000s: the incentives created by a 'consumption' value of schooling imply that income should have become less important over time (or even negatively related to attendance). Instead, the data are more broadly consistent with the hypothesis that more youth are borrowing constrained today than were in the early 1980s.Ability, Achievement, Borrowing Constraints, College, Credit Constraints, Family Income, High School

The Effect of Education on Crime: Evidence from Prison Inmates, Arrests, and Self-Reports

We estimate the effect of high school graduation on participation in criminal activity accounting for endogeneity of schooling. We begin by analyzing the effect of high school graduation on incarceration using Census data. Instrumental variable estimates using changes in state compulsory attendance laws as an instrument for high school graduation uncover a significant reduction in incarceration for both blacks and whites. When estimating the impact of high school graduation only, OLS and IV estimators estimate different weighted sums of the impact of each schooling progression on the probability of incarceration. We clarify the relationship between OLS and IV estimates and show that the 'weights' placed on the impact of each schooling progression can explain differences in the estimates. Overall, the estimates suggest that completing high school reduces the probability of incarceration by about .76 percentage points for whites and 3.4 percentage points for blacks. We corroborate these findings using FBI data on arrests that distinguish among different types of crimes. The biggest impacts of graduation are associated with murder, assault, and motor vehicle theft. We also examine the effect of drop out on self-reported crime in the NLSY and find that our estimates for imprisonment and arrest are caused by changes in criminal behavior and not educational differences in the probability of arrest or incarceration conditional on crime. We estimate that the externality of education is about 14-26% of the private return to schooling, suggesting that a significant part of the social return to education comes in the form of externalities from crime reduction.

Human Capital Formation with Endogenous Credit Constraints

We study the accumulation of human capital and the behavior of consumption and earnings in a life cycle equilibrium model with endogenous borrowing constraints. Constraints arise endogenously from the inalienability of human capital and the limited punishments that creditors are able to impose on those who default. The endogeneity of borrowing constraints produces a number of interesting relationships. First, efficient borrowing limits are functions of individual observable characteristics and choices, especially ability and human capital investments. The connection between human capital investments and borrowing limits creates additional incentives to invest beyond those present in models with exogenous constraints. Second, government policies affect the incentives to default and, hence, the limits on private borrowing. As opposed to exogenous constraint models, additional subsidies for investment in human capital should be accompanied by increases in credit, since borrowers are more able to re-pay higher debts. Finally, general equilibrium considerations have an additional role, since borrowing limits depend on the returns to physical and human capital. We calibrate the model to U.S. data and are able to replicate key features of the economy regarding human capital investment, earnings, and consumption. The calibrated model is then used to study the steady state impacts of changes in government policies. We find that changes in bankruptcy laws can have sizeable effects on the accumulation of both human and physical capital. At the aggregate level, general equilibrium forces are important and can reverse the results predicted in partial equilibrium. Government subsidies to education (financed with a proportional tax on earnings) cause lenders to increase credit limits and substantially increase aggregate human and physical capital. Most importantly, we show that the implications of our model are very different from those of standard exogenous constraint models. For example, the effects of increases in initial wealth and government subsidies on investment are substantially greater in our model than in a similar model with exogenous constraints.

The Impact of Family Income on Child Achievement

Understanding the consequences of growing up poor for a child's well-being is an important research question, but one that is difficult to answer due to the potential endogeneity of family income. Past estimates of the effect of family income on child development have often been plagued by omitted variable bias and measurement error. In this paper, we use a fixed effect instrumental variables strategy to estimate the causal effect of income on children's math and reading achievement. Our primary source of identification comes from the large, non-linear changes in the Earned Income Tax Credit (EITC) over the last two decades. The largest of these changes increased family income by as much as 20%, or approximately $2,100. Using a panel of over 6,000 children matched to their mothers from National Longitudinal Survey of Youth datasets allows us to address problems associated with unobserved heterogeneity and endogenous transitory income shocks as well as measurement error in income. Our baseline estimates imply that a$1,000 increase in income raises math test scores by 2.1% and reading test scores by 3.6% of a standard deviation. The results are even stronger when looking at children from disadvantaged families who are affected most by the large changes in the EITC, and are robust to a variety of alternative specifications.

Electronic properties, low-energy Hamiltonian and superconducting instabilities in CaKFe4_4As4_4

We analyze the electronic properties of the recently discovered stoichiometric superconductor CaKFe$_4$As$_4$ by combining an ab initio approach and a projection of the band structure to a lowenergy tight-binding Hamiltonian, based on the maximally localized Wannier orbitals of the 3d Fe states. We identify the key symmetries as well as differences and similarities in the electronic structure between CaKFe$_4$As$_4$ and the parent systems CaFe$_2$As$_2$ and KFe$_2$As$_2$. In particular, we find CaKFe4As4 to have a significantly more quasi-two-dimensional electronic structure than the latter systems. Finally, we study the superconducting instabilities in CaKFe$_4$As$_4$ by employing the leading angular harmonics approximation (LAHA) and find two potential A$_{1g}$-symmetry representation of the superconducting gap to be the dominant instabilities in this system.Comment: 17 pages, 10 figure