Left-Side strong increases in risk and their comparative statics

This paper introduces a new concept of left-side strong increases in risk (L-SIR) that extends the definition of strong increases in risk (SIR). We also provide somewhat stronger restrictive set of risk-averse decision-makers with a non-negative third derivative utility (prudence) to obtain an appealing comparative statics result for L-SIR.The authors gratefully acknowledge the helpful comments and suggestions of an anonymous referee     

The responsibility of public welfare in family planning

The primary objective of the paper is the implementation of family planning programs in and by the public sector. Providing health service is the category that family planning falls into within public welfare. Only 700,000 patients are now receiving family planning services from all public and private agencies combined. This is only 13% of the target population. All too many policy statments have been made with little done to implement them. The estimation is that in 1966 and 1967 HEW spent about three million dollars on family planning. Public programs have progressed farther through Office of Economic Opportunity than through HEW. Religious sources are the strongest opposition to welfare involvement in family planning. Social work as a profession has a role in family planning to the extent that it considers its role helping people and enhancing family functioning.     

Lebensstile und Wohnstandortwahl

Life style research and various disciplines dealing with regional studies argue that life styles are explanatory relevant for decisions in different behavioral areas, in particular for residential choices. However, the results of previous research are rather mixed. To specify the conditions for the explanatory relevance of life style based preferences for locational choices, this article ties in with a parsimonious decision theoretic model, which has been applied both in the sociology of the city and in life style research. Based on this theoretical framework an empirical study is presented, which tests the explanatory relevance of life styles for residential choices. The study is based on neighborhood survey data from Leipzig, representing a context, in which a strong impact of life styles may be expected. However, even in this context the empirical study shows rather limited explanatory power of life style based preferences for residential choices, whereas household arrangements and economic resource endowments of persons show much more explanatory power.     

An Examination of the Relationship Among High School Size,Social Capital,and Adolescents' Mathematics Achievement

In an effort to enhance both adolescents' social capital and increase achievement, public school districts across the United States have created small high schools. Using data derived from a longitudinal and nationally representative study of U.S. high school students, the Educational Longitudinal Study of 2002, results show that when adolescents' parents know their friends' parents math achievement is significantly predicted. This association, however, is nonsignificant when conditioned on standard measures of prior achievement and family background, among others. In addition, while this relationship is also strong and significant within small high schools, it, too, is eliminated when conditioned on select confounding variables. These findings are discussed in terms of current efforts to improve achievement through reductions in school size.     

Day care in working-class ethnic neighborhoods: implications for social policy.

Implications for social service planning are contained in the findings of a survey to determine preferences in day care for children in working-class families of Polish and Italian extraction.     

Quantitative Risk Estimation for a Legionella pneumophila Infection Due to Whirlpool Use

Quantitative microbiological risk assessment was used to quantify the risk associated with the exposure to Legionella pneumophila in a whirlpool. Conceptually, air bubbles ascend to the surface, intercepting Legionella from the traversed water. At the surface the bubble bursts into dominantly noninhalable jet drops and inhalable film drops. Assuming that film drops carry half of the intercepted Legionella, a total of four (95% interval: 1–9) and 4.5×10⁴ (4.4×10⁴ – 4.7×10⁴) cfu/min were estimated to be aerosolized for concentrations of 1 and 1,000 legionellas per liter, respectively. Using a dose‐response model for guinea pigs to represent humans, infection risks for active whirlpool use with 100 cfu/L water for 15 minutes were 0.29 (～0.11–0.48) for susceptible males and 0.22 (～0.06–0.42) for susceptible females. A L. pneumophila concentration of ≥1,000 cfu/L water was estimated to nearly always cause an infection (mean: 0.95; 95% interval: 0.9–～1). Estimated infection risks were time‐dependent, ranging from 0.02 (0–0.11) for 1‐minute exposures to 0.93 (0.86–0.97) for 2‐hour exposures when the L. pneumophila concentration was 100 cfu/L water. Pool water in Dutch bathing establishments should contain <100 cfu Legionella/L water. This study suggests that stricter provisions might be required to assure adequate public health protection.     

On optimising the estimation of high quantiles of a probability distribution

One of the major aims of one-dimensional extreme-value theory is to estimate quantiles outside the sample or at the boundary of the sample. The underlying idea of any method to do this is to estimate a quantile well inside the sample but near the boundary and then to shift it somehow to the right place. The choice of this “anchor quantile” plays a major role in the accuracy of the method. We present a bootstrap method to achieve the optimal choice of sample fraction in the estimation of either high quantile or endpoint estimation which extends earlier results by Hall and Weissman (1997) in the case of high quantile estimation. We give detailed results for the estimators used by Dekkers et al. (1989). An alternative way of attacking problems like this one is given in a paper by Drees and Kaufmann (1998).     

Book notes

THE SOCIETAL SUBJECT edited by N. Engelsted, M. Hedegaard, B. Karpatscholf, and A. Mortensen. Aarhus: Aarhus University Press, 1993. $26.00.

UNDERSTANDING PRACTICE: PERSPECTIVES ON ACTIVITY AND CONTEXT edited by S. Chaiklin and J. Lave. Cambridge: Cambridge University Press, 1993. $59.95.

THE CULTURAL‐HISTORICAL DEVELOPMENT OF VERBAL THINKING by Peeter Tulviste (Translated by M. J. Hall; Preface by M. Cole). Commack, NY: NOVA Science Publishers, 1991. 183 pp. + notes and references. $39.00.     

中国经济发展机制及其解释

本文从中国经济现实出发 ,阐释了以土地集体所有、个人使用的农业制度为基础的中国经济 ,在以消除剩余劳动力为特征的经济发展过程中可能表现出来的若干基本趋势 ,从而提出了中国经济长期发展的一种可能机制