Distribution and Poverty Impacts of Tax Structure Reform in Developing Countries: How Little We Know

The past two decades have witnessed widespread reforms of tax structures in developing countries. This article reviews available evidence on the effects of various taxes, and hence of tax structure reform, on distribution and the poor. Taxes on exports and goods consumed especially by the poor (e.g. kerosene) are the most consistently found to be regressive, whereas taxes on ‘luxury’ items such as cars, beverages and alcohol are the most likely to be progressive. Sales taxes are slightly more progressive, or less regressive, than taxes on imports. The reforms implemented are therefore unlikely to have worsened the effects of the tax structure on the poor.     

D-optimal mixture component-amount designs for quadratic and cubic models

When the total amount of a mixture of ingredients needs to be taken into account (in addition to the composition of its ingredients), an experimental design requires several levels of the amount. Designs for such situations are discussed, and D-optimal choices are made for fitting quadratic and cubic models, for various numbers of experimental units.     

Inspection errors in graff-roeloffs modification of hierarchical dorfman screening procedures

Graff and Roeloffs' (1972) modification of the Dorfman (1943) screening procedure, and their analysis of the effects of inspection error on properties of the procedure, is extended to hierarchical procedures, using the results of Kotz and Johnson (1982).     

Modeling Supply Chain Dynamics: A Multiagent Approach*

A global economy and increase in customer expectations in terms of cost and services have put a premium on effective supply chain reengineering. It is essential to perform risk-benefit analysis of reengineering alternatives before making a final decision. Simulation provides an effective pragmatic approach to detailed analysis and evaluation of supply chain design and management alternatives. However, the utility of this methodology is hampered by the time and effort required to develop models with sufficient fidelity to the actual supply chain of interest. In this paper, we describe a supply chain modeling framework designed to overcome this difficulty. Using our approach, supply chain models are composed from software components that represent types of supply chain agents (e.g., retailers, manufacturers, transporters), their constituent control elements (e.g., inventory policy), and their interaction protocols (e.g., message types). The underlying library of supply chain modeling components has been derived from analysis of several different supply chains. It provides a reusable base of domain-specific primitives that enables rapid development of customized decision support tools.     

Development and Assessment of Measures of Adolescents' Attitudes about Sexual Relationship Rights

Objective: Develop and validate measures of adolescents' attitudes about sexual relationship rights. Methods: Items were completed by students in a large U.S. city (N = 655). The authors conducted an exploratory factor analysis, evaluated internal consistency, and assessed construct validity, including ability to predict sexual behavior at 1-year follow-up. Results: Factor analysis identified 2 distinct factors, comprising attitudes about rights to refuse unwanted sexual activity (5 items) and express sexual engagement needs (5 items) in a sexual relationship. The measures showed sound evidence of reliability and construct validity. Conclusions: The psychometric evidence supports the use of these measures in adolescent sexual health research.     

Application of the Back Propagation Neural Network Algorithm with Monotonicity Constraints for Two-Group Classification Problems*

Neural network techniques are widely used in solving pattern recognition or classification problems. However, when statistical data are used in supervised training of a neural network employing the back-propagation least mean square algorithm, the behavior of the classification boundary during training is often unpredictable. This research suggests the application of monotonicity constraints to the back propagation learning algorithm. When the training sample set is preprocessed by a linear classification function, neural network performance and efficiency can be improved in classification applications where the feature vector is related monotonically to the pattern vector. Since most classification problems in business possess monotonic properties, this technique is useful in those problems where any assumptions about the properties of the data are inappropriate.     

Cyberbullying,conflict management or just messing? Teenage girls’ understandings and experiences of gender,friendship, and conflict on Facebook in an Irish second-level school

In recent years, there have been growing concerns worldwide about young people’s safety online, much of which focuses on social media sites such as Facebook and Instagram. Moral panics about sexting and cyberbullying have constructed public discourses about social media as dangerous to adolescents’ safety and relationships. In the academic literature, there are conflicting perspectives on the nature of online relationships, behaviour, and risks, and on the causes and nature of cyberbullying. Less attention is paid—in both public and academic debates—to the role played by gender in online aggression, in spite of the fact that existing scholarship demonstrates that it is an important factor in the dynamics of young people’s online friendships and conflicts. This article presents the findings of an empirical, qualitative and quantitative study of teenage girls’ experiences and understandings of online friendship, conflict, and bullying in an Irish, single-sex secondary school. Questionnaires (n=116), individual in-depth interviews with students (n=26), and a focus group with teachers were used. Our study indicates that significant communicative phenomena within girls’ everyday lives remain unreported and frequently misunderstood.     

The impact of specific occupation on mortality in the U.S. National Longitudinal Mortality Study

We compare mortality differences for specific and general categories of occupations using a national cohort of approximately 380,000 persons aged 25-64 from the U.S. National Longitudinal Mortality Study. Based on comparisons of relative risk obtained from Cox proportional-hazards model analyses, higher risk is observed in moving across the occupational spectrum from the technical, highly skilled occupations to less-skilled and generally more labor-intensive occupations. Mortality differences obtained for social status groups of specific occupations are almost completely accounted for by adjustments for income and education. Important differences are shown to exist for selected specific occupations beyond those accounted for by social status, income, and education. High-risk specific occupations include taxi drivers, cooks, longshoremen, and transportation operatives. Low-risk specific occupations include lawyers, natural scientists, teachers, farmers, and a variety of engineers.     

从"西方马克思主义"到西方"马克思学"——诺曼·莱文教授访谈录

诺曼·莱文是当代美国著名的马克思主义研究者,他以极端的“马克思恩格斯对立论”立场而闻名,这一主题贯穿了他从《可悲的骗局:马克思反对恩格斯》(1975年)到《不同的道路:马克思主义和恩格斯主义中的黑格尔》(2006年)的全部重要著作。1981年,中央编译局杜章智先生在《马列著作编译资料》第14辑上对莱文的《可悲的骗局》一书进行了详细的摘编和评论,莱文的观点在我国学界产生了很大影响。莱文所指认的马克思与恩格斯的思想关系问题,从根本上说是如何理解马克思主义的实质、如何理解马克思主义发展中的继承与创新问题;从更大的历史视角着眼,则是关于马克思主义哲学的发展道路问题。因此,这是十分重要的问题。近20年来,国内学界对莱文的学术观点尤其是他的马克思恩格斯对立论多有批判,本刊在2005年第1期发表的《马克思主义哲学视域中的恩格斯——纪念恩格斯逝世110周年笔谈》中曾对此问题进行了一些思考,对莱文的观点也有所涉及。但由于缺乏必要的历史和学术背景资料,相关的研究还有待深入。有鉴于此,本刊本期发表张亮博士最近对莱文先生的访谈录。在访谈中,莱文教授比较详细地介绍了其思想发展历程及主要学术观点。尽管本刊并不认同莱文教授的某些观点,但我们认为本文对于了解马克思恩格斯对立论的历史形成、20世纪美国马克思主义研究的历史与现状、“西方马克思主义”在美国的流变、西方“马克思学”的兴起等具有重要参考价值。我们希望以此把马克思主义哲学史研究中的这一重要问题引向深入,从而推动马克思主义哲学的发展。