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161.
The American diet has changed substantially over the last few decades. These changes provide a test for social theory and have substantial effects on the demand for various food products, thus impacting U.S. agriculture. In this paper a rapidly growing dietary choice—vegetarianism—is explored. Prevalence of various forms of vegetarianism is estimated in a representative sample of a suburban population and factors that influence choice of a vegetarian diet are examined. About 7 percent of the sample report they are vegetarians. The prevalence of vegetarianism is not influenced by age, gender, or education, but individuals holding traditional values are less likely to be vegetarian than others. There also is some evidence mat individuals holding altruistic values are more likely than others to be vegetarians.  相似文献   
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The problem of determining the number of multi-type protection devices and their locations on electrical supply tree networks with subtree dependency is investigated. The aim is to reduce the amount of inconvenience caused to customers that are affected by any given fault on the networks. An appropriate implementation of tabu search is proposed. We exploit a variable neighborhood and a soft aspiration level, and we embed a data structure and reduction tests into the search to speed up the process. Computational tests are performed on randomly generated electrical tree networks varying in size and branch complexity with encouraging results.  相似文献   
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Childhood parental loss and adult depression   总被引:2,自引:0,他引:2  
Previous research demonstrates convincingly that childhood parental deaths and parental divorces have implications for adult well-being as defined by levels of depression, educational attainment, early age at marriage, and risk of divorce. What this research has failed to examine are the interconnections among these outcomes. Specifically, are the socioeconomic and marital outcomes of parental loss implicated in the observed higher levels of depression? This analysis takes a first step in answering this question. Using data from a sample of 1,755 married men and women, I estimated regression models which examine the extent to which adult socioeconomic status and current marital quality mediate and/or modify the loss-depression relationship. Parental divorce was strongly related to socioeconomic and marital outcomes. Furthermore, current marital quality contributed importantly to understanding the higher levels of depressed mood observed among persons from divorced homes. Parental death was much more weakly related to socioeconomic and marital outcomes, and these outcomes played little role in explaining its relationship to depression. Finally, all of these relationships were stronger among women than men. These findings support the utility of life-course approaches to understanding adult mental health.  相似文献   
167.
This paper describes specific transference and counter-transference issues that commonly emerge in therapeutic work with adolescents and parents who are in the midst of family transitions such as divorce and remarriage. Psychoanalytic understanding and definitions of transference and countertransference are applied to short-term family-centered cases in which the parent-adolescent relationship is at particular risk. Case vignettes are presented in order to illustrate how transference and countertransference may guide or interfere with clinical interventions that are especially indicated with adolescents whose family structure has changed. Such interventions as well as the use of consultation are briefly described.At the time this paper was prepared, Ms. Springer was Associate Director and a senior clinician at the Center for the Family in Transition in Corte Madera, California. Funds for the research and clinical work that provided the basis for this paper were supplied by grants from the San Francisco Foudation. An earlier version of this paper was presented at the 66th Annual Meeting of the American Orthopsychiatry Association, New York City, March 31–April 4, 1989.  相似文献   
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The EM algorithm is a popular method for maximizing a likelihood in the presence of incomplete data. When the likelihood has multiple local maxima, the parameter space can be partitioned into domains of convergence, one for each local maximum. In this paper we investigate these domains for the location family generated by the t-distribution. We show that, perhaps somewhat surprisingly, these domains need not be connected sets. As an extreme case we give an example of a domain which consists of an infinite union of disjoint open intervals. Thus the convergence behaviour of the EM algorithm can be quite sensitive to the starting point.  相似文献   
170.
Ethics can be divided into a theory of prudential values and a theory of morality in a narrower sense. My paper proposes a utilitarian — a rule-utilitarian — theory of morality. But it deviates from most of the utilitarian tradition by rejecting the hedonistic and subjectivistic accounts of prudential values favored by many utilitarian writers. While economists tend to define people's utility levels in terms of their actual preferences, ethics must define them in terms of their informed preferences. To prefer A over B does not mean to have a stronger desire for A than for B. Rather, it means to regard one's access to A as being more important than one's access to B. Even though different people often have quite different preferences, their basic desires seem to be much the same. We must choose our moral rules, and our society's moral code as a whole, by their social utility. An important factor in determining their social utility are their expectation effects. Unlike the rule — utilitarian more code, the act — utilitarian moral code would be unable to give proper weight to these expectation effects. It would also unduly restrict our individual freedom. Finally, I shall argue against Kant that morality is primarily a servant of many other human values rather than itself the highest value of human life.  相似文献   
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