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941.
We consider the problem of UMVU estimation of a U-estimable function of four unknown truncation parameters based on two independent random samples from two two-truncation parameter families. In particular, we obtain the UMVU estimator of functional, P (Y > X). Also the confidence intervals for some parametric functions are obtained. 相似文献
942.
Most models for incomplete data are formulated within the selection model framework. Pattern-mixture models are increasingly seen as a viable alternative, both from an interpretational as well as from a computational point of view (Little 1993, Hogan and Laird 1997, Ekholm and Skinner 1998). Whereas most applications are either for continuous normally distributed data or for simplified categorical settings such as contingency tables, we show how a multivariate odds ratio model (Molenberghs and Lesaffre 1994, 1998) can be used to fit pattern-mixture models to repeated binary outcomes with continuous covariates. Apart from point estimation, useful methods for interval estimation are presented and data from a clinical study are analyzed to illustrate the methods. 相似文献
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944.
945.
We model the performance of DMUs (decision-making units) using a two-stage network model. In the first stage of production DMUs use inputs to produce an intermediate output that becomes an input to a second stage where final outputs are produced. Previous black box DEA models allowed for non-radial scaling of outputs and inputs and accounted for slacks in the constraints that define the technology. We extend these models and build a performance measure that accounts for a network structure of production. We use our method to estimate the performance of Japanese banks, which use labor, physical capital, and financial equity capital in a first stage to produce an intermediate output of deposits. In the second stage, those deposits become an input in the production of loans and securities investments. The network estimates reveal greater bank inefficiency than do the estimates that treat the bank production process as a black box with all production taking place in a single stage. 相似文献
946.
This study compared the socioeconomic status, racial composition, and ethnic composition of 49 randomly selected U.S. cities with those of the census tracts containing the solid waste disposal facilities and sewage treatment plants for those cities. Contrary to the environmental racism and classism hypotheses, residents of tracts with landfills or incinerators had higher incomes and were less likely to be minority group members than residents of the cities that generated the refuse—although they did have somewhat lower education levels. There were few differences between the population characteristics of the cities and the census tracts that contained their sewage treatment plants. Possible explanations for these findings are discussed. 相似文献
947.
Bradley R. Brenner Heather Z. Lyons Ruth E. Fassinger 《The Career development quarterly》2010,58(4):321-335
An initial test and validation of a model predicting perceived organizational citizenship behaviors (OCBs) of lesbian and gay employees were conducted using structural equation modeling. The proposed structural model demonstrated acceptable goodness of fit and structural invariance across 2 samples (ns = 311 and 295), which suggested that altruistic OCB performance is precipitated by workplace outness. Furthermore, stigmatization salience and organizational climate for heterosexism predict levels of workplace outness. Organizational climate for heterosexism is negatively related to stigmatization salience. When the model was tested on 2 samples, all structural paths except 1 were significant. 相似文献
949.
950.
Frank R. Wake 《Journal of sex research》2013,50(3):170-177
The purpose of the experiment was to examine the acquisition of information about sexuality by 182 ninth‐grade students enrolled in a sex education course. An additional 197 ninth‐grade students in the same school served as a control group. Approximately half the subjects in each group were pretested. Following completion of the course, all subjects were posttested. The major results of the multiple regression analysis indicated that the experimental group scored higher on the posttest than the control group both for the total set of items (N = 24) and for several subscores measuring learning of sex education material. The pretest and posttest scores did not differ for control group subjects. The results indicated: (a) sex education courses can provide important information about sexuality which is not gained in other ways by ninth‐graders; (b) peers may not be important sources of sexual information when alternatives (sex education courses) to peer information are available. 相似文献