Classification Improvements in Automated Gunshot Residue (GSR) Scans

Classification of particles as gunshot residues (GSRs) is conducted using a semiautomatic approach in which the system first classifies particles based on an automatic elemental analysis, and then, examiners manually analyze particles having compositions which are characteristic of or consistent with GSRs. Analyzing all the particles in the second stage is time consuming with many particles classified by the initial automated system as being potentially GSRs excluded as such by the forensic examiner. In this paper, a new algorithm is developed to improve the initial classification step. The algorithm is based on a binary tree that was trained on almost 16,000 particles from 43 stubs used to sample hands of suspects. The classification algorithm was tested on 5,900 particles from 23 independent stubs and performed very well in terms of false positive and false negative rates. A routine use of the new algorithm can reduce significantly the analysis time of GSRs.     

The unexpected effect of social status on reproduction: a case study in Joseon Korea from the nineteenth to the twentieth centuries

We examine how parents have made decisions about the number of children they have, given their social status in accordance with residential location (either urban or rural areas) and time (either the pre-modern or modern periods). We use two sets of microdata – Jokbo and Jejeokbu – spanning the early nineteenth to mid-twentieth centuries in Korea. Combining the two data-sets, we use multiple imputation to fill the missing entries of some observations and apply a Poisson regression model on the augmented data. Our empirical results reveal statistically significant evidence that higher socioeconomic status is related to having more children. Additionally, our findings indicate that: (1) all else being constant, among high-status people, rural residents had more children than urban families; (2) for people born between 1800 and 1945, those born closer to the 1940s tended to have fewer children; and (3) during modernization, there was still a significant trend for high-status families to have more children.     

The influence of job assignment on community engagement: bicycle patrol and community-oriented policing

The purpose of this study is to compare a specialized community-oriented policing (COP) unit to a reactive unit on officer perceptions of public contact and officer perceptions of job performance. We also compare bicycle patrol officers to motor vehicle patrol officers within these units. Using a static group comparison design, questionnaires were distributed to officers within the Toronto Police Service (n = 178). Bicycle patrol is associated with more contacts with the public and higher rates of proactive policing when compared to motor vehicle patrol and bicycle officers are more likely to rate higher on several measures of crime control. Officers with a COP mandate engage with the public for a wider variety of reasons compared to those with a reactive mandate, and are more likely to rate higher on perceptions of performing job duties in a procedurally just manner. This study demonstrates the value of a specialized COP unit that includes bicycle patrol in achieving tenets of COP. It contributes to the literature on COP and the use of bicycle patrol in law enforcement by presenting the perspective of the police officer.     

An Empirical Analysis of the Acceptance of E-Procurement in the German Public Sector

The increasing governmental spending and simultaneously declining income of municipality are two of the most significant challenges of the 21^st century. The introduction of the Internet and innovative information and communication tools over the last few decades have led to a cost saving and efficiency advantage in many areas. By far, public administration has not fully profited from these opportunities and advantages. This article seeks to understand the underlying barriers of technology implementation, namely e-procurement, within the public administration area by analyzing the key barriers of central decision makers within the organization. The empirical findings of 289 respondents from the German public administration show that the barrier typologies are identified and that they have a strong impact on the resistance of implementation. However, the collected data could not verify the theoretically postulated relationship between high resistance and low implementation of the new technology.     

Intent to Exit: Why Do US Federal Employees Leave?

This study examines factors that may influence an employee to exit an organization. Factors that are considered to influence exit are derived primarily from Hirschman’s model of exit, voice, loyalty, and neglect. Other variables considered are public service motivation, job satisfaction, pay satisfaction, gender, race, supervisory status, and agency. The study evaluates the relationships between these variables using data obtained from the United States’ 2010 Federal Employee Viewpoint Survey. Overall, the data suggest that there is a slight tendency of public employees to be intrinsically motivated.     

基于腰椎高度X线测量技术推断四川汉族女性身高

目的通过腰椎高度X线测量技术,建立四川汉族女性身高的数学模型,为法医人类学研究积累基础数据。方法收集206例四川汉族女性个体按年龄分为A、B、C 3组,其中A组(206例)不分年龄,B组(116例)为20~45岁,C组(90例)为45岁以上,并应用计算机X线摄影(computer radiography,CR)技术分别测量所有样本腰椎CR片中5个椎体(L1~L5)前缘、后缘、中央高度(x1~x15),脊柱腰段中央总长度(x16),同时测量每个个体真实身高,对各测量指标联合与身高的相关性进行线性回归分析,建立推断身高的数学模型,并重新选取62例样本代入数学模型,检验模型的准确性。结果所建立的数学模型经线性回归模型假设检验,均具有统计学意义(P0.05),回归方程的推断标准误为2.982~5.004cm,相关系数为0.370~0.779,复相关系数为0.533~0.834。对每组相关系数、复相关系数最高的方程进行回代检验,其中A组的y=100.33+1.489 x3-0.548 x6+0.772 x9+0.058 x12+0.645 x15的准确率最高,为80.6%(±1SE)、100%(±2SE)。结论本研究建立的数学模型适用于推断四川汉族女性身高。     

Does the Likely Demographics of Affordable Housing Justify NIMBYism?

ABSTRACT

NIMBYism (not in my backyard) decreases the amount of affordable housing construction. A possible motivator for this is an existing homeowner’s fear that proximity to affordable housing depresses property value. Using a hedonic regression analysis of the sales prices of homes in Sacramento County, California, this study finds that increases in the demographic characteristics in a census tract that are likely to increase if more affordable housing is built there lower the sales price of a home. This finding holds even after controlling for the percentages of racial/ethnic groups more likely to face discrimination. Policymakers should recognize this economic element of NIMBYism as they consider instruments to increase the amount of affordable housing built. We conclude with a suggestion for a knowingly controversial policy mechanism based upon cap and trade with the hope it will spur further debate on this issue.     

The Social Outcomes of Education and Feedbacks on Growth in Africa

Most of the effects of education included in the complete model presented here are shown to be consistent with those found in the mainstream of the research on each outcome using microeconomic data. This, however, is a first effort to estimate net education effects more comprehensively, beyond just growth and health effects on other key measures of development in Africa, and also a new view of indirect feedbacks on economic growth and of externalities. After developing the conceptual framework, the regression estimates are presented together with a discussion of the net direct and indirect effects of education on each outcome. These are shown to improve infant mortality, increase longevity, strengthen civic institutions and democratisation, increase political stability, and increase investment in physical capital, which in turn have positive delayed feedback effects on the economic growth process. The effects also lower fertility rates and population growth rates but the latter occurs only after long delays because of the short-term positive effects of education on health. There are significant net education effects reducing poverty, inequality and crime, the latter after netting out negative externalities from growth and white-collar crime. Education effects reducing poverty and substituting skills for extractive exports also contribute to environmental sustainability. Simulations solve the complete model endogenously and iteratively over time for all of the direct and indirect (largely externality) effects. They reveal that indirect feedback effects including those on non-market outcomes are larger than the direct effects. Some effects are immediate, but many of the lags are long. So policy options for a continent in crisis that consider these lags are considered.     

An Exploratory Analysis of Fertility Differentials in India

The association between improving economic conditions and declining growth of population has led economists and demographers to hypothesise a direct relationship between indicators of economic development and fertility rates. Using recent National Family Health Survey data and the 1991 Census to explore factors contributing to fertility rates in India, we found that economic variables explain 70 per cent of the interstate variations in India's fertility rates. However, several non-economic variables explain an even greater proportion, for example, indicators of female autonomy explain 84 per cent of the variations. Our analysis demonstrates that to successfully explain Indian fertility rates, models must rely heavily on non-economic variables.     

Intramedia Mediation: The Cumulative and Complementary Effects of News Media Use

This study focuses on one often overlooked political communication-based media effect, intramedia mediation, and the indirect effects that stem from relationships that exist among various forms of media use. Data from a 2000 national Annenberg election panel survey are used to assess a series of relationships between television and newspaper public affairs use and how these forms of media consumption affect citizens' knowledge of presidential campaign endorsements. The indirect effects that stem from the relationships that exist among these two forms of media use reflect the cumulative and complementary functions of mass communication consumption across time. An analysis of intramedia mediation in coordination with the study of the direct effects of public affairs media use on this study's outcome variable produces substantially larger overall effects for both forms of news use. Thus, the study of intramedia mediation contributes to a better understanding of the full range of media influences on a given outcome variable over the course of a political campaign. Ramifications of these findings are outlined and future lines of research summarized.