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991.
The primary goal of this study is to examine the association between marijuana use and adult depressive symptomatology. The key independent variables examined are age of marijuana initiation, frequency of current marijuana use, the use of other licit and illicit drugs, and whether marijuana was used to cope with problems. The relationships among these variables are assessed using data from the Young Men and Drugs Survey (n = 1,941), a nationally representative sample of men from the 1944-1954 birth cohort. Results show that early marijuana initiation appears to be weakly associated with increased depression in adulthood. This effect, however, is mediated by educational attainment, employment status, marital status, and other drug use, notably alcohol and tobacco use. Adult frequency of marijuana use is not significantly associated with increased depression in adulthood. Finally, marijuana users who use the drug to cope with problems are more depressed than those who do not use to cope with problems.  相似文献   
992.
Recent changes in public policy reflect increased efforts to scapegoat poor women and children and to polarize the objectives of child protection and family preservation. This article challenges various stakeholders in the child welfare field to move beyond the quick-fix solutions and bureaucratic overregulation precipitated by horror stories of child abuse in the media. The new century presents an opportunity to pursue differential intervention strategies that protect children while empowering poor families and communities.  相似文献   
993.
Experiments with incentives in telephone surveys   总被引:4,自引:0,他引:4  
In an effort to counter the problem of noncooperation, survey organizations are offering incentives to respondents with increasing frequency, some at the outset of the survey, as has traditionally been done in mail surveys, and some only after the person has refused, in an attempt to convert the refusal. This article reports on a series of experiments carried out over a period of about 2 years with a monthly telephone survey, the Survey of Consumer Attitudes, in an effort to increase response rates or reduce interviewer effort. We report on experiments with prepaid versus promised incentives; advance letters; and advance letters with prepaid incentives; and we also report on the effects of incentives on response quality, sample composition, response bias, interviewer and respondent expectations, and costs.  相似文献   
994.
This paper questions why with all the traditional inventive genius of the British people, this country is failing to hold its own against foreign competition. While the reasons for this are many, the author suggests that the conventional approach to new product development is a major factor. Industry should put the demands of the consumer first rather than an abstract pursuit of technological development. He suggests that for industry in general the needs of consumers should take precedence over the ‘technology push’.  相似文献   
995.
This paper reviews the planning practices in multinational firms, focusing particularly on the relationship between subsidiaries and head offices during the planning process. It examines the planning problems experienced by multinationals using a simple paradigm to classify problems according to whether their origin was primarily with home office or with subsidiary; with the planning system itself or with the managers involved in running that system.  相似文献   
996.
A multiple objective linear programming (MOLP) method utilizing interval criterion weights is applied to the problem of media selection. Using this technique, it is possible to analyze a problem more explicitly in terms of the several objectives inherent in many media selection situations. In order to illustrate the interval criterion weights approach, a multiple objective hierarchical media selection model is presented and its computer results discussed. In addition to being able to deal more directly with different decision criteria, a distinguishing feature of the mathematical analysis applied here is that its output enables the media-planner to be presented with a small cluster of candidate media schedules (rather than just one). Then, from this list, the media-planner should be in a position to qualitatively make a final choice as a close approximation to his optimal solution.  相似文献   
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Accuracy of the Pearson-Tukey three-point approximation is measured in units of standard deviation and compared with that of Monte Carlo simulation. Using a variety of well-known distributions, comparisons are made for the mean of a random variable and for common functions of one and two random variables. Comparisons are also made for the mean of an assortment of risk-analysis (Monte Carlo) models drawn from the literature. The results suggest that the Pearson-Tukey approximation is a useful alternative to simulation in risk-analysis situations.  相似文献   
1000.
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