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Barro-type endogenous growth models propose a nonmonotonic relationship between productive public spending and growth. Under this so-called nonlinearity hypothesis the size and direction of growth effects due to an increase in public spending depend on the share of public spending in GDP. Employing German time-series data we examine the validity of the nonlinearity hypothesis. We estimate growth effects by using models whose coefficients are allowed to vary with the share of public spending in GDP. Our results support the hypothesis for public consumption but not for public investment data. (JEL H54 , E62 , C22 ) 相似文献
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Michael D. Denkinger Simone E. Flick Thorsten Nikolaus Clemens Becker Kamiar Aminian Ulrich Lindemann 《European review of aging and physical activity》2014,11(2):133-139
Increased physical activity is positively associated with better health in community-dwelling older persons. It is unclear whether physical activity also influences success of inpatient rehabilitation. For the assessment of physical activity in inpatient rehabilitation the Physical Activity in Inpatient Rehabilitation Assessment (PAIR), a short questionnaire based on five questions, was developed and preliminary validated. In this study, the PAIR was validated against a sensor-based physical activity measurement. Seventy functionally impaired and cognitively mostly intact patients of a German geriatric inpatient rehabilitation clinic who had undergone hip surgery (n?=?62 women, median age?=?83 years) participated. Physical activity was measured using the PAIR and a sensor-based activity monitor (Physilog ®; BioAGM, CH). Assessments were conducted at admission (T1) and 2 weeks later (T2) during the rehabilitation process. To assess concurrent and predictive validity, Spearman correlations and linear regression models were calculated using sensor-based walking activity and uptime activity (walking and standing time) as dependent variables. Criterion-related concurrent validity using physical activity sensors was weak to moderate. Correlations were slightly higher at T2 (r?=?0.45-0.53) than at T1 (r?=?0.44-0.46). The objectively measured variance of physical activity, explained by the PAIR, ranged from 25 to 43 %. PAIR activity scores and sensor-based walking or total activity increased in a dose-dependent manner, confirming the scoring system of the PAIR. The application time was usually less than 2 min. The validity of the PAIR is weak to moderate when compared to a sensor-based activity monitor and comparable to existing physical activity assessments for community-dwelling older adults. 相似文献
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Ohne Zusammenfassung 相似文献
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Summary: Wald statistics in generalized linear models are asymptotically 2 distributed.
The asymptotic chi–squared law of the corresponding quadratic form shows disadvantages
with respect to the approximation of the finite–sample distribution. It is shown by means
of a comprehensive simulation study that improvements can be achieved by applying
simple finite–sample size approximations to the distribution of the quadratic form in
generalized linear models. These approximations are based on a 2 distribution with an
estimated degree of freedom that generalizes an approach by Patnaik and Pearson. Simulation studies confirm that nominal level is maintained with higher accuracy compared
to the Wald statistics. 相似文献
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We are concerned with three different types of multivariate chi-square distributions. Their members play important roles as limiting distributions of vectors of test statistics in several applications of multiple hypotheses testing. We explain these applications and consider the computation of multiplicity-adjusted p-values under the respective global hypothesis. By means of numerical examples, we demonstrate how much gain in level exhaustion or, equivalently, power can be achieved with corresponding multivariate multiple tests compared with approaches which are only based on univariate marginal distributions and do not take the dependence structure among the test statistics into account. As a further contribution of independent value, we provide an overview of essentially all analytic formulas for computing multivariate chi-square probabilities of the considered types which are available up to present. These formulas were scattered in the previous literature and are presented here in a unified manner. 相似文献
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Thorsten Berndt 《Soziologie》2006,35(1):113-117
Ohne Zusammenfassung 相似文献
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Corinna Ewelt-Knauer Thorsten Knauer Max Thielemann 《Zeitschrift für Betriebswirtschaft》2014,84(4):571-607
For investment companies, selling a portfolio company represents a critical phase in the investment life cycle. The choice of exit channel (initial public offering, secondary buyout, or trade sale) is of particular importance. This paper analyses factors relevant to exit channel selection, deploying a sample of 1,435 European buyout exits between 1992 and 2010. We differentiate between factors which refer to characteristics of the selling investment company and characteristics of the transaction object. Our analysis yields evidence that the reputation of the selling investment company, syndicate size, quality of the transaction object, as well as partial exit are associated with exit channel type. Moreover, our analysis reveals that the economic context and conditions in the capital markets significantly influence the choice of exit channel. 相似文献
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Data envelopment analysis (DEA) and free disposal hull (FDH) estimators are widely used to estimate efficiency of production. Practitioners use DEA estimators far more frequently than FDH estimators, implicitly assuming that production sets are convex. Moreover, use of the constant returns to scale (CRS) version of the DEA estimator requires an assumption of CRS. Although bootstrap methods have been developed for making inference about the efficiencies of individual units, until now no methods exist for making consistent inference about differences in mean efficiency across groups of producers or for testing hypotheses about model structure such as returns to scale or convexity of the production set. We use central limit theorem results from our previous work to develop additional theoretical results permitting consistent tests of model structure and provide Monte Carlo evidence on the performance of the tests in terms of size and power. In addition, the variable returns to scale version of the DEA estimator is proved to attain the faster convergence rate of the CRS-DEA estimator under CRS. Using a sample of U.S. commercial banks, we test and reject convexity of the production set, calling into question results from numerous banking studies that have imposed convexity assumptions. Supplementary materials for this article are available online. 相似文献