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951.
We show that given a value function approximation V of a strongly concave stochastic dynamic programming problem (SDDP), the associated policy function approximation is Hölder continuous in V.  相似文献   
952.
Many textbooks on project management present illustrations concerning the relative size of project attributes during different project phases. The derived models all have attributes in common, such as uncertainty, significance of decisions, and degree of freedom to maneuver, that are typically high in the beginning of the project and low in the end. At the same time, variables such as the accumulated cost and available information begin at low levels and end up at a high level at the end of the project. Based on empirical data from projects, this paper illustrates and quantifies one of these attributes, the freedom to maneuver, in different project phases.  相似文献   
953.
While it is well recognized that US metropolitan areas are polycentric, there is little consensus as to the appropriate method for identifying concentrations of employment within them. Existing methods suffer from strong assumptions about parametric form, misspecification, or reliance on local knowledge to calibrate model parameters. This paper introduces a new nonparametric method for identifying subcenters. Results indicate that this, more flexible, nonparametric approach yields greater accuracy with regard to both urban and suburban centers compared with other approaches. This approach should provide better data for the numerous topics that depend on the spatial accounting of employment within metropolitan areas.  相似文献   
954.
This article examines relationships between receipt of internal administrative information in hospitals, influence over general management decisions, and the extent to which certain organizational characteristics predict the receipt of information by each of the three major groups in hospitals: the board, the CEO, and the medical staff. Using a US national sample of 287 non-profit community hospitals, CEOs were found to receive the greatest amount of information and had highest influence while medical staffs were lowest on both measures. of five major organizational characteristics, hospital size emerged as the single strongest predictor of receipt of information for both boards (beta =?0.28, p 0.001) and medical staffs (beta =?0.42, p 0.001). Overall, the five dependent variables explained 18 per cent of the variance in receipt of information by boards and 28 percent of the variance for medical staffs.  相似文献   
955.
This article examines judicial and administrative rulings and legislation involving or related to the issue of drug testing in the workplace. It discusses the rights of employees in the public and private sector: constitutional rights; federal, state, and local statutory rights; rights of unionized employees; and common law rights. It analyzes both the current state of the law and future directions the law may take, as courts and administrative agencies decide more cases and governmental bodies continue to pass drug testing legislation.  相似文献   
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N. Mukhopadhyay 《Metrika》1977,24(1):197-201
Asymptotic normality of the stopping time ofMukhopadhyay [1976] relating to the point estimation problem is proved. Also moderate sample size behaviour of this stopping time has been studied by Monte-Carlo methods.  相似文献   
960.
Simpler Probabilistic Population Forecasts: Making Scenarios Work   总被引:1,自引:0,他引:1  
The traditional high-low-medium scenario approach to quantifying uncertainty in population forecasts has been criticized as lacking probabilistic meaning and consistency. This paper shows, under certain assumptions, how appropriately calibrated scenarios can be used to approximate the uncertainty intervals on future population size and age structure obtained with fully stochastic forecasts. As many forecasting organizations already produce scenarios and because dealing with them is familiar territory, the methods presented here offer an attractive intermediate position between probabilistically inconsistent scenario analysis and fully stochastic forecasts.  相似文献   
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