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791.

A decomposition technique for quantifying the impacts of changes in product mix and process performance on aggregate process-related indicators is presented. Through application of the technique, the real performance of a process can be quantified. Changes in real performance over time can be monitored to provide useful information for process evaluation and production planning. Two case studies, one related to the aggregate defective rate for an assembly line of an integrated circuit fabrication plant and the other to the aggregate inventory turnover for a tyre distribution company, are presented to illustrate the application of the technique.  相似文献   
792.
The theory and properties of trend-free (TF) and nearly trend-free (NTF) block designs are wel1 developed. Applications have been hampered because a methodology for design construction has not been available.

This article begins with a short review of concepts and properties of TF and NTF block designs. The major contribution is provision of an algorithm for the construction of linear and nearly linear TF block designs. The algorithm is incorporated in a computer program in FORTRAN 77 provided in an appendix for the IBM PC or compatible microcomputer, a program adaptable also to other computers. Three sets of block designs generated by the program are given as examples.

A numerical example of analysis of a linear trend-free balanced incomplete block design is provided.  相似文献   
793.
We use data from the National Longitudinal Survey of Adolescent Health to estimate effects of adolescent girls' overweight on their propensity to engage in risky sexual behavior. We estimate single equation, two‐stage, and sibling fixed‐effects models. We consider both absolute weight and weight relative to other girls in the individual's school. We focus on vaginal intercourse without a condom, any type of sexual activity while under the influence of alcohol, and anal intercourse. Our findings confirm previous research indicating that overweight or obese girls are less likely than their recommended‐weight counterparts to be sexually active. As a result, they are less likely to have vaginal intercourse without a condom. However, overweight or obese girls are not less likely to have sex under the influence of alcohol, and once they have had vaginal intercourse, their consistency of condom use is no different from that of their recommended‐weight peers. The most striking finding is that overweight or obese girls are at least 15% more likely than their recommended‐weight peers to have ever had anal intercourse regardless of whether they have ever had vaginal sexual intercourse. The results from this study underscore the importance of using multifaceted and contemporary measures of risky sexual behavior and have implications for the health and well‐being of adolescent girls. (JEL I12, J13)  相似文献   
794.
Semi‐structured one‐on‐one interviews with 102 gay and bisexual men were conducted to examine the reasoning processes men use to exempt themselves from practicing safe sex. Qualitative analysis of the interviews revealed the following recurring themes: (a) Many men who were in couple relationships avoided condom use for reasons involving intimacy or trust, or because both partners were HIV‐negative; (b) unsafe sex sometimes occurred inadvertently or involuntarily; (c) negative moods and self‐images were associated with unsafe sex; (d) by “intuiting” that their partner was HIV‐negative, participants exempted themselves from the need for safe sex; and (e) when the boundary between safe and unsafe was unclear, participants used a combination of unofficial and official guidelines to determine what is safe.  相似文献   
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A class of goodness-of-fit estimators is found to provide a useful alternative in certain situations to the standard maximum likelihood method which has some undesirable estimation characteristics for estimation from the three-parameter lognormal distribution. The class of goodness-of-fit tests considered include the Shapiro-Wilk and Filliben tests which reduce to a weighted linear combination of the order statistics that can be maximized in estimation problems. The weighted order statistic estimators are compared to the standard procedures in Monte Carlo simulations. Robustness of the procedures are examined and example data sets analyzed.  相似文献   
798.
Much leadership literature neglects its historical-contextual antecedents and as a result over-emphasizes zeitgeist, or tenor of the time's social forces. This neglect impedes leadership research by encouraging academic amnesia and promoting a strong feeling of research déjà vu among many researchers and practitioners. In this article, we develop a leadership historical-contextual superstructure consisting of evolutionary antecedents, paradigmatic antecedents, purpose and definitional antecedents, stakeholder antecedents, levels of analysis and temporal antecedents, and research dissemination antecedents. We use this superstructure to analyze current work in the increasingly important relational leadership research stream to illustrate how the superstructure's use can aid leadership researchers and practitioners in avoiding leadership déjà vu and academic amnesia and help build a more cumulative field.  相似文献   
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Converse's definition of ideological contraint is expanded to provide for various respondent identified ideological dimensions rather than an all encompassing liberal-conservative dimension. Using this redefinition a sample of adults is shown to have high levels of ideological constraint. Ideological constraint is shown to vary with the degree of cognitive complexity and the degree of preference evaluability. The latter is a new concept that suggests that some issues will be easier for a respondent to demonstrate constraint on depending upon the availability and applicability of preference criteria. Salience is also shown to have a positive relationship with ideological constraint, but only when preference evaluability is high.  相似文献   
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