Demographic change, macroeconomic conditions, and the murder rate: The case of the United States, 1934–2006

Fluctuations in aggregate crime rates contrary to recent shifts in the age distribution of the U.S. population have cast doubt on the predictive power of the age–crime hypothesis. By examining a longer time horizon, back to the early 1930s, we show that the percentage of the young population is a robust predictor of the observed large swings in the U.S. murder rate over time. However, changes in the misery index—the sum of the inflation and unemployment rates—significantly contribute to explaining changes in the murder rate. This applies, in particular, to those changes that are at odds with the long-run trend of the U.S. age distribution, such as the decline in the murder rate in the latter part of the 1970s or its increase starting around the middle of the 1980s.     

Conditional interval estimation of the mean following rejection of a two sided test

The effect of rejecting a two-sided preliminary test of significance for the mean of a normal distribution upon subsequent interval estimation of the mean is examined. For the case where the variance is known, conditional confidence intervals may be shorter than unconditional intervals, in contrast to the one-sided preliminary test case examined by Meeks and D’Agostino (1983, The American Statistician, 7, 134-136) . For the case where the variance is unknown and must be estimated by the sample variance, it is shown that customary intervals do not offer uniformly greater or lesser coverage than the nominal level.     

Delayed Adulthood,Delayed Desistance? Trends in the Age Distribution of Problem Behaviors

As the transition to adulthood becomes more protracted and less orderly, fewer young people occupy adult roles and experience the social control associated with these roles. One might therefore expect behaviors associated with the teenage years to spill over into older age groups, reflecting postponed entrance into full social adulthood. We test this hypothesis by examining trends over time in the age distribution of crime, substance use, and violent death. We find little evidence that behaviors typical of adolescence are moving upward to older ages. Although the achievement of adult roles is being pushed to older ages, this stretching of the transition to adulthood is not reflected in the observed patterns of substance use, violent death, and arrests.     

The Protestant Ethic: Weber s Model and the Empirical Literature

Empirical research with regard to the Protestantethic is reviewed in relation to Weber s model of thepart a specifically religious ethos played in the riseof capitalism. Weber argued that Western legal and commercial changes were not in themselvesan adequate explanation. Essential also was the set ofvalues emphasized by ascetic Protestantism:self-discipline, hard work, the careful use of time, the reinvestment of one s gains, personal honesty,creative innovation, and faith in the rewards of a justGod. Empirical research has found positive correlationsbetween Protestant ethic values and internal locus of control (self-discipline), hard work,honesty, and belief in a just world. Findings withregard to the use of time and money are inconclusive.The relationship with creative innovation has not been examined. There is a need for empiricalstudy of the relationship between the Protestant ethicand personal religious orientation.     

Conservatism of the Accident Sequence Evaluation Program HRA Procedure

This paper presents a limited assessment of the conservatism of the Accident Sequence Evaluation Program (ASEP) human reliability analysis (HRA) procedure described in NUREG/CR-4772. The data for this study are derived from simulator examination reports from the NRC requalification examination cycle for nuclear power plant operators. The ASEP procedure was used to estimate human error probability (HEP) values for critical tasks, and the HEP results were compared with the failure rates observed in the examinations. The ASEP procedure was applied by PNNL operator license examiners who supplemented the limited information in the examination reports with expert judgment based upon their extensive simulator examination experience. Comparison of the average of the ASEP HEP values with the fraction of the population actually failed and demonstrated that the ASEP HEP values are larger (conservative) by a statistically significant average factor of two. Partitioning of tasks into subgroups based on the ASEP HEP values and comparison of the subgroup average ASEP HEP values with observed subgroup failure rates showed little or no conservatism for small ASEP HEP values, but considerable conservatism for larger ASEP HEP values.     

Fitting In: Socio-Economic Attainment Patterns of Foreign-Born Egyptians in the United States

This paper analyzes socio-economic attainment patterns of foreign-born Egyptians in the United States, as tabulated in the 1980 U. S. Census. This is achieved first through an examination of their earnings, followed by an analysis of the rate at which their human capital characteristics are converted into wages.
The findings suggest that this more recent immigrant group has likely attained higher earnings largely because of their skills and educational levels. Thus, while assimilation theory posits the crucial importance of time as a linkage to higher socio-economic attainment, this may not necessarily be the case for these immigrant men and women.     

Likelihood analysis for a class of beta mixed models

Beta regression is a suitable choice for modelling continuous response variables taking values on the unit interval. Data structures such as hierarchical, repeated measures and longitudinal typically induce extra variability and/or dependence and can be accounted for by the inclusion of random effects. In this sense, Statistical inference typically requires numerical methods, possibly combined with sampling algorithms. A class of Beta mixed models is adopted for the analysis of two real problems with grouped data structures. We focus on likelihood inference and describe the implemented algorithms. The first is a study on the life quality index of industry workers with data collected according to an hierarchical sampling scheme. The second is a study assessing the impact of hydroelectric power plants upon measures of water quality indexes up, downstream and at the reservoirs of the dammed rivers, with a nested and longitudinal data structure. Results from different algorithms are reported for comparison including from data-cloning, an alternative to numerical approximations which also allows assessing identifiability. Confidence intervals based on profiled likelihoods are compared with those obtained by asymptotic quadratic approximations, showing relevant differences for parameters related to the random effects. In both cases, the scientific hypothesis of interest was investigated by comparing alternative models, leading to relevant interpretations of the results within each context.     

Do females necessarily have the same occupational status scores as males? A conceptual and empirical examination of the Duncan Socioeconomic Status Index and Nam-Powers Occupational Status Scores

Social Science researchers have advanced important yet somewhat contradictory conclusions regarding the different economic and occupational reward structures faced by men and women. Income and wage differences between men and women have been shown to be sizable and persistent throughout the occupational hierarchy. Conversely, gender differences in occupational status, commonly scaled by the Duncan Socioeconomic Index, have been shown to be small or nonexistent in most studies. In an attempt to investigate this incongruity, the present study undertakes a comparison of the Duncan SEI and the Nam-Powers Occupational Status Scores in an empirical study of the occupational position of white men and women in 65 large standard metropolitan statistical areas (SMSAs) in 1970. While the findings of earlier studies showing no gender differences in occupational status are for the most part replicated using the Duncan SEI, use of the Nam-Powers scores prompts a much different conclusion. Large status differences between men and women are indicated using this latter scale, differences which are very much in line with income differences commonly cited. We suggest that the Nam-Powers metric should be used instead of the Duncan SEI in studies of occupational status of women and men.