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31.
Expectations, Capital Gains, and Income 总被引:2,自引:0,他引:2
A theoretical framework for the measurement of income under uncertainty is developed that addresses some long-standing controversies about the treatment of capital gains. The consequences for economic analysis and policy making are potentially serious, because the treatment of capital gains can significantly affect some major macroeconomic aggregates, including national income and savings, balance of payments deficits, government deficits, and depreciation. (JEL O47 , P44 , Q32 ) 相似文献
32.
Craig H. Mallinckrodt John G. Watkin Geert Molenberghs Raymond J. Carroll 《Pharmaceutical statistics》2004,3(3):161-169
Missing data, and the bias they can cause, are an almost ever‐present concern in clinical trials. The last observation carried forward (LOCF) approach has been frequently utilized to handle missing data in clinical trials, and is often specified in conjunction with analysis of variance (LOCF ANOVA) for the primary analysis. Considerable advances in statistical methodology, and in our ability to implement these methods, have been made in recent years. Likelihood‐based, mixed‐effects model approaches implemented under the missing at random (MAR) framework are now easy to implement, and are commonly used to analyse clinical trial data. Furthermore, such approaches are more robust to the biases from missing data, and provide better control of Type I and Type II errors than LOCF ANOVA. Empirical research and analytic proof have demonstrated that the behaviour of LOCF is uncertain, and in many situations it has not been conservative. Using LOCF as a composite measure of safety, tolerability and efficacy can lead to erroneous conclusions regarding the effectiveness of a drug. This approach also violates the fundamental basis of statistics as it involves testing an outcome that is not a physical parameter of the population, but rather a quantity that can be influenced by investigator behaviour, trial design, etc. Practice should shift away from using LOCF ANOVA as the primary analysis and focus on likelihood‐based, mixed‐effects model approaches developed under the MAR framework, with missing not at random methods used to assess robustness of the primary analysis. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
33.
The present article assesses the adversary systemper se and asks the question, Is there any place for courtroom antics and histrionics in cases involving children? Social workers are uncomfortable before the august body of thecourt, not because of any lack of education or knowledge on their part but because of the nature of the adversary process itself. 相似文献
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In our zeal to deal with alcohol and drug abuse, we may have a distorted picture of what the majority of college students actually think about alcohol and drug use. Students in this study done at a public university located in the Deep South report being generally intolerant of substance abuse. 相似文献
37.
38.
Kathleen D. McCarthy 《Voluntas: International Journal of Voluntary and Nonprofit Organizations》1996,7(4):453-456
Ohne Zusammenfassung
German translations by Monika Lütke-Daldrup. 相似文献
39.
John D. Emerson David C. Hoaglin Frederick Mosteller 《Statistical Methods and Applications》1993,2(3):269-290
Summary Meta-analyses of sets of clinical trials often combine risk differences from several 2×2 tables according to a random-effects
model. The DerSimonian-Laird random-effects procedure, widely used for estimating the populaton mean risk difference, weights
the risk difference from each primary study inversely proportional to an estimate of its variance (the sum of the between-study
variance and the conditional within-study variance). Because those weights are not independent of the risk differences, however,
the procedure sometimes exhibits bias and unnatural behavior. The present paper proposes a modified weighting scheme that
uses the unconditional within-study variance to avoid this source of bias. The modified procedure has variance closer to that
available from weighting by ideal weights when such weights are known. We studied the modified procedure in extensive simulation
experiments using situations whose parameters resemble those of actual studies in medical research. For comparison we also
included two unbiased procedures, the unweighted mean and a sample-size-weighted mean; their relative variability depends
on the extent of heterogeneity among the primary studies. An example illustrates the application of the procedures to actual
data and the differences among the results.
This research was supported by Grant HS 05936 from the Agency for Health Care Policy and Research to Harvard University. 相似文献
40.
Craig C. Lundberg 《International Journal of Value-Based Management》1992,5(1):107-117
This paper focuses upon an as yet under-explored factor believed to underlie most managerial and organizational behavior variables—work ideology. Work ideologies are surveyed for several convenience samples of students and managers to show their ability to be studied and that patterned differences may be discovered. In addition, the historical origins and meanings of four major work ideologies are discussed. 相似文献