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61.
The authors examine facilitative aspects of field research with deviant street populations. Based on the authors' research with the homeless and with male street prostitutes, the facilitative aspects include access to settings, social relationships, acquisition of information, and the maintenance of researcher interest. The authors argue that in each of these aspects street deviants may in some ways be easier to study than other populations. The paper concludes with suggestions for maximizing the efficiency and quality of fieldwork with specific deviant populations.  相似文献   
62.
For testing the fit of the inverse Gaussian distribution with unknown parameters, the empirical distribution-function statistic A2 is studied. Two procedures are followed in constructing the test statistic; they yield the same asymptotic distribution. In the first procedure the parameters in the distribution function are directly estimated, and in the second the distribution function is estimated by its Rao-Blackwell distribution estimator. A table is given for the asymptotic critical points of A2. These are shown to depend only on the ratio of the unknown parameters. An analysis is provided of the effect of estimating the ratio to enter the table for A2. This analysis enables the proposal of the complete operating procedure, which is sustained by a Monte Carlo study.  相似文献   
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VII. Conclusion The number of immigrants now coming to the United States is proportionally only a fraction of the number that came in earlier years, and there is nothing in those numbers to suggest a difficult absorption burden. Immigrants, both legal and illegal, more than pay for the services they use with the taxes they pay, leaving a considerable net surplus that benefits American citizens. Immigrants raise productivity and do not cause an observable amount of unemployment of citizens. Admitting far more immigrants into the country than the law now allows would have positive effects on the incomes of citizens, and would enhance the continuing vitality of the United States.  相似文献   
65.
In our zeal to deal with alcohol and drug abuse, we may have a distorted picture of what the majority of college students actually think about alcohol and drug use. Students in this study done at a public university located in the Deep South report being generally intolerant of substance abuse.  相似文献   
66.
Summary Meta-analyses of sets of clinical trials often combine risk differences from several 2×2 tables according to a random-effects model. The DerSimonian-Laird random-effects procedure, widely used for estimating the populaton mean risk difference, weights the risk difference from each primary study inversely proportional to an estimate of its variance (the sum of the between-study variance and the conditional within-study variance). Because those weights are not independent of the risk differences, however, the procedure sometimes exhibits bias and unnatural behavior. The present paper proposes a modified weighting scheme that uses the unconditional within-study variance to avoid this source of bias. The modified procedure has variance closer to that available from weighting by ideal weights when such weights are known. We studied the modified procedure in extensive simulation experiments using situations whose parameters resemble those of actual studies in medical research. For comparison we also included two unbiased procedures, the unweighted mean and a sample-size-weighted mean; their relative variability depends on the extent of heterogeneity among the primary studies. An example illustrates the application of the procedures to actual data and the differences among the results. This research was supported by Grant HS 05936 from the Agency for Health Care Policy and Research to Harvard University.  相似文献   
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This paper focuses upon an as yet under-explored factor believed to underlie most managerial and organizational behavior variables—work ideology. Work ideologies are surveyed for several convenience samples of students and managers to show their ability to be studied and that patterned differences may be discovered. In addition, the historical origins and meanings of four major work ideologies are discussed.  相似文献   
69.
This paper studies a robust approach to the analysis of cell pedigree data, building on the work of Huggins & Marschner (1991) which discussed M-estimation for the so-called bifurcating autoregressive process. The study allows for incomplete observation of the pedigree, and incorporates the possibility of additive effects outliers, as discussed in the time series literature. Some properties of the proposed estimation procedure are studied, including a Monte Carlo investigation of robustness in the presence of contamination.  相似文献   
70.
The theory of family paradigms provides an integrative framework for under-standing and systematizing the diverse ways that families organize and make sense of family life. Using formal methods of analysis based on logical and geometrical arguments, the priecise implications of models of family types can be investigated and compared. The paradigmatic framework can thus be refined and extended to form a more rigorous theoretical grounding for family typologies is explored and a miltidimensional model is derived the geometry of which is equivalent to, but more succinctly captures, the underlying structure of uariation in family para-digms. In Part II, the resulting model is interpredtd and explored in terms of implications for family theory, theory construction, and family therapy. Clarifying the basic dimensions of the paradigmatic framework also permits more precise exploration of interrelationships among related models of family types, which can be understood as reduced models derivable from the complete geometry of the paradigmatic framework.  相似文献   
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