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161.
The purpose of this study is to (1) compare youth entering substance abuse treatment with and without a history of foster care placement to determine any differences in mental health, substance use, and exposure to victimization, and (2) determine if mental health, substance use, and/or exposure to victimization predict past pregnancy among the sample with a history of foster care placement. The pooled dataset consisted of 17,124 adolescents (12-17 years of age) who completed the Global Appraisal of Individual Needs at intake for substance abuse treatment in 2009. Of these, 366 (2.1%) reported having been in foster care in the past year. When compared with a non-foster care sample, the foster care sample reported significantly higher internal mental distress scores, behavior complexity scores, and general victimization scores, after controlling for race, gender, and level of care. Problems associated with substance use did not differ between groups, though regular tobacco use was present at a higher rate in the foster care sample. Multivariate logistic regression results revealed that, within the foster care sample, internal mental distress and gender predicted past pregnancy. There may be room for intervention within substance abuse treatment centers for youth with a history of foster care, who may be at risk for pregnancy if their levels of internal mental distress are high.  相似文献   
162.
Information produced by ERP systems is termed JIT-information, since it is provided at the right time in the right place with a minimum of waste. The JIT-information construct is defined and described and a measurement scale is developed. A JIT-information performance model is proposed and assessed using a structural equation modelling methodology. The results indicate that the model fits the data well: (1) supply chain management strategy positively impacts JIT-information, (2) JIT-information directly impacts both logistics and organisational performance, and (3) logistics performance directly impacts organisational performance.  相似文献   
163.
We evaluated a strategy for making highly nonpreferred work duties more preferred as a potential means of enhancing work enjoyment among supervisors in a human service setting. Repeated preference ratings and rankings were completed by 4 supervisors during baseline to identify their most disliked work tasks. These tasks were then altered by soliciting each supervisor's opinion regarding why the respective task was so disliked and what could be done to make the task more preferable, removing disliked stimuli associated with the tasks, and adding liked stimuli during completion of the tasks. Following the task alterations, ratings of task likeability increased for all 4 supervisors. Preference rankings of target tasks also increased, including from rankings as among the least preferred tasks to among the most preferred tasks. All supervisors rated the task-alteration process as making their quality of work life better, and all chose to continue the intervention. These results occurred without any observed decrease in work quality. Results are discussed regarding the potential contribution of behavioral interventions with subjective concepts, such as enjoyment, that are viewed as important by the general populace. However, qualifications with relying on verbal reports also are noted.  相似文献   
164.
Board members and chief professional officers (CPOs) from the local units of a national nonprofit organization completed questionnaires that revealed (1) statistically significant differences as to what functionsand activities each believes the other should do and does perform, (2) areas of possible tension between boards and their CPOs, and (3) those activities with significant correlations to common performance measures established by the national organization. Both board members and CPOs believe boards should be doing more than they do, with CPOs being more critical of board members than they are of themselves or than board members are of them. There is significant tension between boards and CPOs regarding responsibility for some operational issues. However, neither the presence nor absence of tension was significantly correlated with the effectiveness of the organization. Finally, self‐reported measures of effectiveness correlated with external measures developed by the national organization, providing some evidence that self‐reported measures may be valid.  相似文献   
165.
166.
Factors influencing Soay sheep survival   总被引:4,自引:0,他引:4  
We present a survival analysis of Soay sheep mark recapture and recovery data. Unlike previous conditional analyses, it is not necessary to assume equality of recovery and recapture probabilities; instead these are estimated by maximum likelihood. Male and female sheep are treated separately, with the higher numbers and survival probabilities of the females resulting in a more complex model than that used for the males. In both cases, however, age and time aspects need to be included and there is a strong indication of a reduction in survival for sheep aged 7 years or more. Time variation in survival is related to the size of the population and selected weather variables, by using logistic regression. The size of the population significantly affects the survival probabilities of male and female lambs, and of female sheep aged 7 or more years. March rainfall and a measure of the North Atlantic oscillation are found to influence survival significantly for all age groups considered, for both males and females. Either of these weather variables can be used in a model. Several phenotypic and genotypic individual covariates are also fitted. The only covariate which is found to influence survival significantly is the type of horn of first-year female sheep. There is a substantial variation in the recovery probabilities over time, reflecting in part the increased effort when a population crash was expected. The goodness of fit of the model is checked by using graphical procedures.  相似文献   
167.
Given spatially located observed random variables ( x , z = {( x i , z i )} i , we propose a new method for non-parametric estimation of the potential functions of a Markov random field p ( x | z ), based on a roughness penalty approach. The new estimator maximizes the penalized log-pseudolikelihood function and is a natural cubic spline. The calculations involved do not rely on Monte Carlo simulation. We suggest the use of B-splines to stabilize the numerical procedure. An application in Bayesian image reconstruction is described.  相似文献   
168.
After a brief review of the role of dummy variables in regression analysis and the current state-of-the art in rounding/truncation error detection in computerized least squares programs, this paper presents a theorem that can be used to detect this type of error whenever an analyst is running a regression program that has one (or more) dummy variables as independent variables.  相似文献   
169.
A model for measuring subjective evaluations of multiple component alternatives is developed and tested in the context of business students' evaluations of professorial candidates for tenured positions. The model is based on a type of ANOVA formulation in which the response variable need only be rank ordered. That is, arbitrary monotonic functions of subjective responses can be made that optimize a well-defined badness of fit measure. Application of the model indicates that metric analysis of the response data can exhibit a large number of configural (interaction) effects that may be a reflection of how subjects use rating scales rather than anything more basic in their combination of multiple component cues. Implications of these findings for the modeling of multiple component choices are discussed.  相似文献   
170.
We use data from an Internet-based survey and estimate the benefits of an oyster consumption safety policy with the contingent valuation method. In addition to providing a context-specific estimate of willingness-to-pay for oyster safety, we consider an important issue in the contingent valuation mortality risk reduction literature. A number of studies find that willingness-to-pay for mortality risk reduction is not sensitive to the scope of the risk change. We present the scope test as a difference in the number of lives saved by the program, instead of small changes in risk, and find that referendum votes are responsive to scope. A third feature of this article is that we identify those at-risk respondents who would most benefit from the policy and decompose willingness-to-pay into use values and altruistic nonuse values. We find that willingness-to-pay per life saved ranges from $3.95 million to $7.69 million for the private good of lives saved when the respondent is at risk (i.e., use values). Willingness-to-pay per life saved including both use and altruistic nonuse values ranges from $6.89 million to $12.87 million.  相似文献   
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