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921.
922.
Most studies of burnout have focused on lack of resources, prevalence of burnout, and negative outcomes. In contrast, this study examined the relationships among altruism, burnout and a positive outcome, namely, the engagement in organizational citizenship behaviour. Web questionnaires were distributed to employees in three professional organizations. The results from the 178 respondents indicated that altruism is related to organizational citizenship behaviour. Of the three dimensions of burnout, only reduced personal accomplishment was (negatively) associated with engagement in organizational citizenship behaviours. Implications of the results are discussed and directions for future research are offered. 相似文献
923.
This paper examines modeling and inference questions for experiments in which different subsets of a set of k possibly dependent components are tested in r different environments. In each environment, the failure times of the set of components on test is assumed to be governed by a particular type of multivariate exponential (MVE) distribution. For any given component tested in several environments, it is assumed that its marginal failure rate varies from one environment to another via a change of scale between the environments, resulting in a joint MVE model which links in a natural way the applicable MVE distributions describing component behavior in each fixed environment. This study thus extends the work of Proschan and Sullo (1976) to multiple environments and the work of Kvam and Samaniego (1993) to dependent data. The problem of estimating model parameters via the method of maximum likelihood is examined in detail. First, necessary and sufficient conditions for the identifiability of model parameters are established. We then treat the derivation of the MLE via a numerically-augmented application of the EM algorithm. The feasibility of the estimation method is demonstrated in an example in which the likelihood ratio test of the hypothesis of equal component failure rates within any given environment is carried out. 相似文献
924.
925.
We present a method for estimating transmission matrices that describe the mixing and the probability of infection between age groups. Transmission matrices can be used to estimate age-dependent forces of infection in age-structured, compartmental models for the study of infectious diseases. We analyze the social network generated by the synthetic population of Portland and extract mixing patterns. Our results show that the mixing within the population consists of two groups, children and adults. Children interact most frequently with other children close to their own age, while adults interact with a wider range of age groups and the durations of typical adult contacts are shorter than typical contacts between children. Furthermore, the transmission matrix shows that children are more likely to acquire infection than adults. 相似文献
926.
Björn Häckel 《Zeitschrift für Betriebswirtschaft》2008,78(9):969-977
Die Forderung nach schwacher Wertadditivit?t von Sicherheits?quivalenten ist in Abh?ngigkeit des jeweiligen Bewertungszwecks
zu diskutieren. W?hrend in der unternehmensexternen Bewertungssicht, z.B. bei der Unternehmensbewertung, die Forderung nach
schwacher Wertadditivit?t gut begründbar ist, stellt sie im Bereich der unternehmensinternen Steuerungssicht eine „Nice to
have“-Anforderung dar. Darüber hinaus werden in der bisherigen Literatur zur Anwendbarkeit von Sicherheits?quivalenten die
Kernherausforderungen der unternehmensinternen Steuerung vernachl?ssigt. Insbesondere die ad?quate Berücksichtigung stochastischer
Abh?ngigkeiten im Portfolioverbund bei der Bewertung von Einzelgesch?ften mittels Sicherheits?quivalenten stellt eine Forschungslücke
dar. 相似文献
927.
928.
Testing the Significance of Categorical Predictor Variables in Nonparametric Regression Models 总被引:2,自引:0,他引:2
In this paper we propose a test for the significance of categorical predictors in nonparametric regression models. The test is fully data-driven and employs cross-validated smoothing parameter selection while the null distribution of the test is obtained via bootstrapping. The proposed approach allows applied researchers to test hypotheses concerning categorical variables in a fully nonparametric and robust framework, thereby deflecting potential criticism that a particular finding is driven by an arbitrary parametric specification. Simulations reveal that the test performs well, having significantly better power than a conventional frequency-based nonparametric test. The test is applied to determine whether OECD and non-OECD countries follow the same growth rate model or not. Our test suggests that OECD and non-OECD countries follow different growth rate models, while the tests based on a popular parametric specification and the conventional frequency-based nonparametric estimation method fail to detect any significant difference. 相似文献
929.
930.
Michael H. LeRoy 《Journal of Labor Research》1991,12(4):453-466
In this study of the acceptance by union members of drug testing in the workplace, 919 union members from 13 major unions
were asked what drug-testing policy, if any, they preferred. Respondents evaluated particular aspects of a hypothetical drug-testing
program. The results show that a large majority of union members agree with a limited drug-testing policy. Five theoretical
models of union member attitudes were extrapolated to the drug-testing context and were examined by using discriminant function
analysis. No support was found for the individual demographics theory, but empirical support was found for some elements of
instrumental union, bargaining outcomes, general normative attitude, and workplace conditions theory. The discriminant function
was 80.56 percent successful in classifying union members who accept drug testing. 相似文献