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991.
We examine the relative importance of tax rates and macroeconomic fluctuations in explaining the share of national adjusted gross income (AGI) reported by the top 0.5% of all taxpayers. Results indicate that cutting the top income or capital gains tax rate would increase the top AGI share but not by enough to increase revenues. The preponderance of evidence suggests that the top AGI share is affected more by the capital gains tax rate than by the income tax rate but that real gross domestic product fluctuations have even larger effects. 相似文献
992.
The present article deals with the problem of estimation of parameters in a linear regression model when some data on response
variable is missing and the responses are equi-correlated. The ordinary least squares and optimal homogeneous predictors are
employed to find the imputed values of missing observations. Their efficiency properties are analyzed using the small disturbances
asymptotic theory. The estimation of regression coefficients using these imputed values is also considered and a comparison
of estimators is presented. 相似文献
993.
This paper shows how to construct confidence bands for the difference between two simple linear regression lines. These confidence bands provide directly the information on the magnitude of the difference between the regression lines over an interval of interest and, as a by-product, can be used as a formal test of the difference between the two regression lines. Various different shapes of confidence bands are illustrated, and particular attention is paid towards confidence bands whose construction only involves critical points from standard distributions so that they are consequently easy to construct. 相似文献
994.
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
995.
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
996.
997.
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
998.
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
999.
1000.