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81.
Experiments Testing Multiobject Allocation Mechanisms   总被引:2,自引:0,他引:2  
This paper reports the results of over 130 auctions conducted under controlled conditions to examine the robustness of several auction mechanisms to allocate multiple objects. The simultaneous discrete auction process used by the Federal Communications Commission to allocate Personal Communications licenses was contrasted with a sequential auction and a combinatorial auction over a variety of demand conditions. In test environments created to check only the minimum competency of the procedures, the simultaneous discrete auction process produces highly efficient allocations, approaching levels similar to those found with a continuous form of the auction, and it outperforms a sequential auction. However, in environments created to stress test the procedures, a combinatorial auction outperforms the simultaneous discrete auction.  相似文献   
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Background: Validation of overall survival (OS) extrapolations of immune-checkpoint inhibitors (ICIs) during the National Institute for Health and Care Excellence (NICE) Single Technology Assessment (STA) process is limited due to data still maturing at the time of submission. Inaccurate extrapolation may lead to inappropriate decision-making. The availability of more mature trial data facilitates a retrospective analysis of the plausibility and validity of initial extrapolations. This study compares these extrapolations to subsequently available longer-term data.

Methods: A systematic search of completed NICE appraisals of ICIs from March 2000 to December 2017 was performed. A targeted search was also undertaken to procure published OS data from the pivotal clinical trials for each identified STA made available post-submission to NICE. Initial Kaplan-Meier curves and associated extrapolations from NICE documentation were extracted to compare the accuracy of OS projections versus the most mature data.

Results: The review identified 11 STAs, of which 10 provided OS data upon submission to NICE. The extrapolations undertaken considered parametric or piecewise survival models. Additional data cut-offs provided a mean of 18 months of OS beyond the end of the original data. Initial extrapolations typically under-estimated OS from the most mature data cut-off by 0.4–2.7%, depending on the choice of assessment method and use of the manufacturer- or ERG-preferred extrapolation.

Conclusion: Long-term extrapolation of OS is required for NICE STAs based on initial immature OS data. The results of this study demonstrate that the initial OS extrapolations employed by manufacturers and ERGs generally predicted OS reasonably well when compared to more mature data (when available), although on average they appeared to underestimate OS. This review and validation shows that, while the choice of OS extrapolation is uncertain, the methods adopted are generally aligned with later-published follow-up data and appear appropriate for informing HTA decisions.  相似文献   

84.
The European Treaty supports the application of the polluter pays principle in all environmental policies including the Water Framework Directive. This paper assesses the efficiency of water-charging systems in two European regions. The regions examined are the South west region of Ireland and the Navarre region in Spain which were selected because they are similar in terms of economic indicators but different in terms of water pricing structures. The paper describes the development and application of a simple model to analyse data on water-charging systems from these two regions. We present the results of a detailed scenario-based investigation illustrating the differences between experience, composition and basis, impact and constraints on the application of water charges for both regions. The key findings are that existing water charges do not provide incentives for users to use water efficiently and thereby do not contribute effectively to the environmental objectives of the Water Framework Directive.  相似文献   
85.
Managed care, once celebrated as a vehicle to halt the increasing cost of health care, has come under increasing fire from patients and health care providers, accused of cutting costs and managing care at the expense of patients. The Employee Retirement Income Security Act of 1974 (ERISA) has been a shield for managed care organizations (MCOs), buffeting them from liability for quality-of-care issues. Lawsuits and legislation are chipping away at the protective shield of ERISA as MCOs find themselves more liable for their decisions and for the care provided by physicians with whom the MCO contracts and provides financial incentives for controlling cost of medical care.  相似文献   
86.
Understanding the emergence of innovation systems is recently put central in research analysing the process of technological change. Especially the key activities that are important for the build up of an innovation system receive much attention. These are labelled ‘functions of innovation systems’. This paper builds on five empirical studies, related to renewable energy technologies, to test whether the functions of innovation systems framework is a valid framework to analyse processes of technological change. We test the claim that a specific set of functions is suitable. We also test the claim made in previous publications that the interactions between system functions accelerate innovation system emergence and growth. Both claims are confirmed.  相似文献   
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In typical experiments on ultimatum bargaining, the game is described verbally and the majority of subjects deviate from subgame-perfect behavior. Proposers typically offer significantly more than the minimum possible and Responders reject “unfair” offers. In this work, we show that when the ultimatum bargaining game is presented as an abstract game tree, the vast majority of behavior is consistent with individualistic preferences and subgame-perfection. This finding raises doubts about theories that ignore the potential influence of social context and experiments that do not control for social context.  相似文献   
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