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This paper considers the effects of informative two-stage cluster sampling on estimation and prediction. The aims of this article are twofold: first to estimate the parameters of the superpopulation model for two-stage cluster sampling from a finite population, when the sampling design for both stages is informative, using maximum likelihood estimation methods based on the sample-likelihood function; secondly to predict the finite population total and to predict the cluster-specific effects and the cluster totals for clusters in the sample and for clusters not in the sample. To achieve this we derive the sample and sample-complement distributions and the moments of the first and second stage measurements. Also we derive the conditional sample and conditional sample-complement distributions and the moments of the cluster-specific effects given the cluster measurements. It should be noted that classical design-based inference that consists of weighting the sample observations by the inverse of sample selection probabilities cannot be applied for the prediction of the cluster-specific effects for clusters not in the sample. Also we give an alternative justification of the Royall [1976. The linear least squares prediction approach to two-stage sampling. Journal of the American Statistical Association 71, 657–664] predictor of the finite population total under two-stage cluster population. Furthermore, small-area models are studied under informative sampling. 相似文献
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We study nonparametric estimation of the illness-death model using left-truncated and right-censored data. The general aim is to estimate the multivariate distribution of a progressive multi-state process. Maximum likelihood estimation under censoring suffers from problems of uniqueness and consistency, so instead we review and extend methods that are based on inverse probability weighting. For univariate left-truncated and right-censored data, nonparametric maximum likelihood estimation can be considerably improved when exploiting knowledge on the truncation distribution. We aim to examine the gain in using such knowledge for inverse probability weighting estimators in the illness-death framework. Additionally, we compare the weights that use truncation variables with the weights that integrate them out, showing, by simulation, that the latter performs more stably and efficiently. We apply the methods to intensive care units data collected in a cross-sectional design, and discuss how the estimators can be easily modified to more general multi-state models. 相似文献
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Yair Berson Louise A. Nemanich David A. Waldman Benjamin M. Galvin Robert T. Keller 《The Leadership Quarterly》2006,17(6):577
We review theoretical and empirical work relevant to the nexus of leadership with organizational learning. We build on the classic distinction between exploration and exploitation and the 4I framework of organizational learning [Crossan, M. M., Lane, H. W., & White, R. E. (1999). An organizational learning framework: From intuition to institution. Academy of Management Review, 24, 522–537.] to present previous research and offer research directions linking leadership constructs and processes of organizational learning at different levels of analysis. For each of these links, we discuss the mediating effect of organizational context and suggest future research directions. This review is integrated using a model and propositions that depict the role of leaders with regard to new and existing learning. 相似文献
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This study focused on the associations between individual variations in children’s motor abilities and individual differences in social participation and play behavior. Indoor and outdoor play behavior patterns of 88 kindergarten children were observed, and a battery of standard assessments of basic motor functions was administered. The findings indicate significant associations between children’s motor abilities and social and nonsocial forms of play. Results are discussed in relation to existing conceptual models of the underlying causes for nonsocial behavior. 相似文献
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This study examined trust that public servants have in citizens. We build on the reciprocal nature of trust and applied Structural Equation Modeling (SEM) to test both the antecedents to public servants?? trust in citizens (e.g., job satisfaction, organizational commitment, organizational politics, public sector motivation and generalized trust) and several of its potential outcomes (exit, voice, loyalty, neglect and cynicism) among Israeli civic servants. A revised and improved model found that organizational politics and generalized trust are the strongest predictors of public servants?? trust in citizens and that exit intention is its major outcome. Implications and suggestions for future studies are presented. 相似文献
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Quantitative Assessment of the Risk of Release of Foot‐and‐Mouth Disease Virus via Export of Bull Semen from Israel 下载免费PDF全文
A. Meyer L. Zamir A. Ben Yair Gilboa B. Gelman D. U. Pfeiffer T. Vergne 《Risk analysis》2017,37(12):2350-2359
Various foot‐and‐mouth disease (FMD) virus strains circulate in the Middle East, causing frequent episodes of FMD outbreaks among Israeli livestock. Since the virus is highly resistant in semen, artificial insemination with contaminated bull semen may lead to the infection of the receiver cow. As a non‐FMD‐free country with vaccination, Israel is currently engaged in trading bull semen only with countries of the same status. The purpose of this study was to assess the risk of release of FMD virus through export of bull semen in order to estimate the risk for FMD‐free countries considering purchasing Israeli bull semen. A stochastic risk assessment model was used to estimate this risk, defined as the annual likelihood of exporting at least one ejaculate of bull semen contaminated with viable FMD virus. A total of 45 scenarios were assessed to account for uncertainty and variability around specific parameter estimates and to evaluate the effect of various mitigation measures, such as performing a preexport test on semen ejaculates. Under the most plausible scenario, the annual likelihood of exporting bull semen contaminated with FMD virus had a median of 1.3 * 10?7 for an export of 100 ejaculates per year. This corresponds to one infected ejaculate exported every 7 million years. Under the worst‐case scenario, the median of the risk rose to 7.9 * 10?5, which is equivalent to the export of one infected ejaculate every 12,000 years. Sensitivity analysis indicated that the most influential parameter is the probability of viral excretion in infected bulls. 相似文献
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THE OPTIMAL TAXATION OF ASSET INCOME WHEN GOVERNMENT CONSUMPTION IS ENDOGENOUS: THEORY,ESTIMATION AND WELFARE 下载免费PDF全文
Michael Ben‐Gad 《Economic inquiry》2017,55(4):1689-1711
This paper derives the Ramsey optimal fiscal policy for taxing asset income in a model where government expenditure is a function of net output or the inputs that produce it. Extending work by Kenneth L. Judd, I demonstrate that the canonical result that the optimal tax on capital income is zero in the medium to long term is a special case of a more general model. Employing a vector error correction model to estimate the relationship between government consumption and net output or the factor inputs that generate it for the United States between 1948Q1 and 2015Q4, I demonstrate that this special case is empirically implausible, and show how a cointegrating vector can be used to determine the optimal tax schedule. I simulate a version of the model using the empirical estimates to measure the welfare implications of changing the tax rate on asset income, and contrast these results with those generated in a version of the model where government consumption is purely exogenous. The shifting pattern of welfare measurements confirms the theoretical results. I calculate that the prevailing effective tax rate on net asset income in the United States between 1970 and 2014 averaged 0.449. Hence abolishing the tax completely does generate welfare improvements, though only by the equivalent of between 1.103% and 1.616% permanent increase in consumption—well under half the implied welfare benefit when the endogeneity of the government consumption is ignored. The maximum welfare improvement from shifting part of the burden of tax from capital to labor is the equivalent of a permanent increase in consumption of between only 1.491% and 1.858%, and is attained when the tax rate on asset income is lowered to between 0.148 and 0.186. Allowing the tax rate to vary over time raises the maximum welfare benefit to 1.865%. All the results are very robust to a wide range of elasticities of labor supply. (JEL E62, H21, H50) 相似文献
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Information economics models evaluate the value of information under the assumption that decision makers wish to maximize their expected payoff. This assumption has been criticized for not being realistic enough since decision makers usually consider more than one business objective and might be satisficers rather than optimizers. This paper attempts to apply an information economics model to decision situations where two business performance criteria, expected payoff and risk, are considered. In order to overcome the difficulty of unknown trade-off between the two criteria, one criterion is used as an objective to be optimized, while the other is set as a constraint. This may be interpreted as a combination of optimizing and satisficing approaches. It is shown how an information system can be evaluated in terms of both expected payoff and risk. The model suggests the trade-off between the two criteria as an additional trait of an information system. In the last part of the paper, a numerical example illustrates how a comparative evaluation of information structures is performed when risk minimization and expected payoff maximization are concurrently used as business performance criteria. 相似文献