A relation for the covariances of order statistics from n independent and non-identically distributed random variables

We derive a simple relation satisfied by the covariances of order statistics in the i.i.d. case and then generalize it to the case when the variables are independent and non-identically distributed. This relation could be employed successfully either to check the calculations or to reduce the amount of direct computations involved in evaluating the covariances of order statistics from an outlier model.     

The right to life

In this issue is a lengthy, thought-provoking essay on the issues raised by unwanted pregnancy. Written by Robert Wennberg in 1984 for the Christian Scholar's Review (13:4), the article has been edited and condensed for our purposes and is quite relevant, I believe, for the student health population. Any practitioner who cares for students wrestling with these issues should at least acknowledge the moral and philosophical dilemmas presented. As one who has walked both sides of the argument, I find Wennberg's fair-mindedness compelling. In closing his article, the author raises the question of what will happen when it becomes possible to accomplish an "abortion"--or removal of the fetus from the mother--without killing the fetus. Will this procedure be acceptable to the average single college student? The New York Times, in an article on "High Tech Babies" (February 21, 1986), raised ethical questions posed by the technology of frozen embryos. Who decides what is to be done with frozen embryos? To whom do they belong? Do they have rights? The theoretical issues raised by Wennberg are already forcing themselves upon us. Whether we like it or not, the future is now. Regardless of your beliefs on this controversial topic, I urge you to read this article. Dr. Wennberg has also just completed a book on this subject, Life In The Balance.     

Immigration and the earnings of youth in the U.S.

"This article reports findings that have emerged from an effort made at statistically measuring the effects of immigration on the earnings of U.S.-born youth. The presence of immigrants arriving before 1965 has a positive impact on youth earnings. Recently arrived immigrants impact negatively, however. These results are consistent with recent findings that the skill level of immigrants arriving within the last two decades is lower relative to that of immigrants arriving earlier. The results also show that the negative effects diminish as the youth ages, reflecting skill acquisition and job mobility of the young worker into jobs less vulnerable to competition from immigrant workers."     

The technique of participatory research in community development

The technique of participatory research in community development is based on the involvement of the beneficiaries of the research in the entire research process, including the formulation of the research design, the collection of data, interpretation of information collected, and the analysis of findings. Thus, research teams utilizing this approach are composed of villagers, farmers, unemployed people, local leaders, and educators. The research process thus offers an educational experience that helps to identify community needs and motivate community members to become committed to the solution of their own problems. Moreover, this approach challenges the prevalent notion that only professional researchers can generate knowledge for meaningful social reform. A participatory research technique, based on the concept of citizen enlightenment for community development, was adopted by the Department of Adult Education at the University of Ibadan in a study of rural poverty in Oyo State's Apasan villages. The research team, comprised of local leaders, peasant farmers, teachers, local students, and university students, identified the villages' isolation and food scarcity as major causes of poverty. 2 actions were taken in response to these findings: 1) the construction of a road linking the Apasan communities with the State capital, enabling villagers to travel to the town, sell their goods, and purchase needed items; and 2) formation of a primary cooperative society for multipurpose farming. These actions have solved the food problem, improved the villagers' earning capacity, and resulted in the return of numerous villagers who had migrated to towns to find wage employment. Because the villagers were directly involved in the study of their problems, they were able to become more aware of their social reality and make the changes needed to lift them out of poverty.     

Black and white population change in small American suburbs since World War II: regional differences

"This study examines the relationship between black population concentration (% black), black population change and white population change for small American suburbs for the 1950-1980 period. Linear, tipping point (curvilinear) and interaction models of racial transition are evaluated for each decade by region (South and non-South), controlling for several other suburban characteristics (age, annexation and distance to the Central Business District) which may affect both black and white population change. The analyses show that racial transition in suburbs involves the parallel development of white and black populations with mainly weak and complex causal linkages which are sensitive to broader suburbanization patterns."     

Compulsive gambling and the medical model

The medical model as a conceptual and operative approach to compulsive gambling is discussed. The terms medical model and disease are defined and the practical implications of their application to compulsive gambling are explored. Special attention is given to the addictive disease concept. Finally, a variety of objections to the medical model are described, but it is concluded that the many individual and social advantages of the medical model make it the preferred conceptualization at our present state of knowledge.     

Dealing with uncertainty: statistics for an aging population

"Uncertainty in statistics and demographic projections for aging and other policy purposes comes from four sources: differences in definitions, sampling error, nonsampling error, and scientific uncertainty. Some of these uncertainties can be reduced by proper planning and coordination, but most often decisions have to be made in the face of some remaining uncertainty. Although decision makers have a tendency to ignore uncertainty, doing so does not lead to good policy-making. Techniques for estimating and reporting on uncertainty include sampling theory, assessment of experts' subjective distributions, sensitivity analysis, and multiple independent estimates." The primary geographical focus is on the United States.     

Birth control in the early stage of marriage

Results are presented from a 1985 survey containing questions on family planning conducted among 13,392 newly married couples in Poland during the period from two to six months following marriage. The opinions of husbands and wives concerning various methods of contraception are analyzed.