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81.
William F. Northey Vicky Primer Lisa Christensen 《Child and Adolescent Social Work Journal》1997,14(1):5-22
Caught between their child and doing the right thing, families of chronic juvenile delinquents often experience a series of injustices in the name of justice. Attempts by the system to correct the delinquency problem often result in the imposition of values and beliefs that negate the family's values, experiences and meanings of their child's behavior. The Ecosystemic Natural Wrap-around (E.N.W.) model attempts to respectfully account for the many influences that maintain problematic interactions, both internal and external, in the nuclear family of chronic juvenile delinquents. The model focuses on a variety of interventions at different levels and contexts, building on the strengths of the family, using the extended family and fictive kin networks, and clarifying the meanings associated with problematic behavior for the multiple players. The model proposed is an integrative theoretical approach, emphasizing systems theory and constructivism. 相似文献
82.
83.
The Community Prevention Trial was 5-year effort to reduce alcohol-involved injuries and death through a comprehensive program of community awareness and policy activities. The three experimental communities were of approximately 100,000 population each (one in Northern California, one in Southern California, and one in South Carolina). Matched comparison communities were used for each experimental community. This article describes the evaluation approach used in a program that sought to change environmental factors not a specific population or target group. This approach demanded unique evaluation approaches for determining overall community aggregate effects, that is, distal outcomes, as well as changes in key mediating variables, that is, process effects. The problem of trending and lagged effects of community prevention programs are discussed. 相似文献
84.
This article provides recommendations and observations about evaluation of a locally based prevention project to reduce problems at a total community or aggregate level. The shift from targeting specific individuals or subpopulations to the overall structure and environment of a community is most demanding. Evaluation tools and analysis techniques have lagged behind program development because community-level interventions are not linked to a specific target group who can be separately studied. Thus assumptions about using random assignment and/or comparison communities as means to control for confounding variables are weakened when the unit of analysis is the community itself and dependent measures are subject to trending and the effects of history. 相似文献
85.
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88.
Using data from the 1984 panel of the Survey of Income and Program Participation (SIPP), this article examines characteristics of the older population disaggregated by net-worth quintiles. The authors argue that income is not a sufficient measure of economic status for current policy discussions on issues such as changing Medicare co-payments, increasing the taxation of social security benefits, or means-testing under Medicaid. Net worth is a better measure of economic status, particularly for the elderly, because it represents the net value of assets accumulated over the life course. Their results indicate that there is considerable diversity in the economic status of the older population, which is masked by aggregate statistics (such as means and medians) typically used to summarize the economic status of population groups. Stereotypical views of the elderly based on such aggregates result in misdirected policy formulation. In the future, policymakers will need to formulate policies and programs using information on the distributions of income and assets among the older populations rather than relying on statistical aggregates. 相似文献
89.
Little is known about why nonprofits accrue debt, how much they owe, and whether the funds they borrow are used productively. This article distinguishes between productive, problematic, and deferred debt. Employing a data base representative of 114,726 tax-filing charitable nonprofits in the United States in 1986, it examines the pervasiveness of nonprofit debt and the relation between this debt and nonprofit financial health. The analysis finds that over 70 percent of the nonprofits hold debt, the distribution of this debt is highly concentrated, and the level of debt and leverage varies with asset size and type of activity. Nonprofits with higher leverage and absolute debt levels are financially healthier than those with lower levels. While the analysis does not determine whether financially stronger nonprofits are better able to borrow, the results support the view that borrowing in the nonprofit sector is economically efficient. 相似文献
90.
Summary We consider a lotL formed byN apparently similar unitsW
1,…,W
N, where each of theW
i may come from one of two different populationsP
1 andP
2;T
1,…,T
N denote the corresponding lifetimes. The units fromP
i
undergo a failure of kindi and their survival function isS
i
(t).
We assume that the failure rate function
F02589067_TeX2GIFIE1.gif" alt="
$$\lambda _i (t) = - \frac{d}{{dt}}\log S_i (t) (i = 1,2)$$
" align="middle" border="0">
are known and that the units fromP
1 are ?substandard?: λ
1
(t)≥λ
2
(t), ∀t≥0.
We want to putW
1,…,W
N under a pre-operational test (burn-in test) in order to eliminate at least a great part of the substandard units and we face
the problem of obtaining a rule for stopping the test under the assumption that, with the failure of a unit, it is possible
to recognize the population from which the unit comes.
Such a problem will be formalized as an optimal stopping problem for a suitably defined Markov process. Our study shall evidentiate
some fundamental aspects of the problem and the role of the prior distribution of the (random) numberM
0 of those units inL coming fromP
1 (substandard). The latter distribution has a great influence on the form of the solution.
This research was supported by the C.N.R. Project ?Statistica Bayesiana e Simulazione in Affidalità e Modellistica Biologica?. 相似文献