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91.
Ventilator-associated pneumonia (VAP) accounts for the majority of nosocomial pneumonias, which may increase intensive care and prolonged hospital stays. Endotracheal tubes allowing continuous subglottic suctioning may reduce VAP; however, they are more expensive than standard endotracheal tubes not allowing continuous suctioning. he objective of this study was to measure the comparative costs associated with continuous subglottic suctioning endotracheal tubes (CSS-ETT) versus standard endotracheal tubes (S-ETT) among intubated patients and whether cost differential is offset by the occurrence of VAP in patients receiving either type of intubation. A retrospective chart review was conducted for 154 intubated adult patients (77 = S-ETT; 77 = CSS-ETT). The S-ETT group had one case of VAP; the CSS-ETT group had none. The mean total hospital charges were higher for the S-ETT group ($103,600; CSS-ETT= $88,500) (p = 0.3). Although the average number of intubation days and ICU days were greater for the CSS-ETT group, there were no cases of VAP compared to the S-ETT group. ased upon the one S-ETT VAP case and the VAP attributable costs, it is cost effective to use the CSS-ETT.  相似文献   
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We seek to isolate in the laboratory factors that encourage and discourage the sunk cost fallacy. Subjects play a computer game in which they decide whether to keep digging for treasure on an island or to sink a cost (which will turn out to be either high or low) to move to another island. The research hypothesis is that subjects will stay longer on islands that were more costly to find. Eleven treatment variables are considered, e.g. alternative visual displays, whether the treasure value of an island is shown on arrival or discovered by trial and error, and alternative parameters for sunk costs. The data reveal a surprisingly small sunk cost effect that is generally insensitive to the proposed psychological drivers. Electronic Supplementary Material Supplementary material is available in the online version of this article at . Jel Classification C91, D11  相似文献   
95.
A dual representation of a technology, e.g., a cost function, may not contain all of the technological information, but it will contain all of the information about input vectors that would be chosen by a cost-minimizing firm. At least this much is clear for deterministic technologies. The main question addressed in this paper is whether the same can be said about stochastic technologies and their dual representations. Despite some pessimism expressed in the stochastic frontier literature on this question, we argue that there is no extra cost imposed in the stochastic case. Thus, the conclusion of this paper is: Just dual it!  相似文献   
96.
Stimulated by the availability of large sets of microeconomic data, research on the economics of time use has been a growth industry in the past 20 years. That growth has included studies that have focused on the effect of people's value of time; on the mix of nonmarket activities that they undertake; on the interactions of spouses’ choices of time use; on the valuation of nonmarket time, and on the timing of nonmarket and market activities. By laying out these research questions and indicating their importance, this essay provides a framework for a series of meta‐analyses.  相似文献   
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This paper introduces a new measure, based on a study by Trucost and Dr Robert Repetto, combining external environmental costs with established measures of economic value added, and demonstrates how this measure can be incorporated into financial analysis. We propose that external environmental costs are relevant to all investors: universal investors are concerned about the scale of external costs whether or not regulations to internalise them are likely; mainstream investors need to understand external costs as an indication of future regulatory compliance costs; and SRI investors need to evaluate companies on both financial and social performance. The paper illustrates our new measure with data from US electric utilities and illustrates how the environmental exposures of different fund managers and portfolios can be compared. With such measures fund managers can understand and control portfolio‐wide environmental risks, demonstrate their environmental credentials quantitatively and objectively and compete for the increasing number of investment mandates that have an environmental component.  相似文献   
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This article operationalizes a non-empty relation as implied if strict preference and indifference jointly do not completely order the choice set. Specifically, indecision is operationalized as a positive preference for delegating choice to a least predictable device.  相似文献   
99.
Detecting nonlinearity in time series by model selection criteria   总被引:1,自引:0,他引:1  
This article analyzes the use of model selection criteria for detecting nonlinearity in the residuals of a linear model. Model selection criteria are applied for finding the order of the best autoregressive model fitted to the squared residuals of the linear model. If the order selected is not zero, this is considered as an indication of nonlinear behavior. The BIC and AIC criteria are compared to some popular nonlinearity tests in three Monte Carlo experiments. We conclude that the BIC model selection criterion seems to offer a promising tool for detecting nonlinearity in time series. An example is shown to illustrate the performance of the tests considered and the relationship between nonlinearity and structural changes in time series.  相似文献   
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