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61.
Taxation of Mobile Factors as Insurance under Uncertainty   总被引:1,自引:0,他引:1  
This paper considers the effects of the taxation of mobile factors, i.e., capital, under uncertainty. The wages earned by residents of a jurisdiction are uncertain due to random shocks. Since the uncertain wages in a jurisdiction depend on the amount of mobile capital employed in the jurisdiction, and since taxation alters the quantity of capital employed, taxation affects the riskiness of uncertain wages. In particular, the taxation of capital moderates the fluctuation of uncertain wages, thereby providing insurance. For this reason, jurisdictions use distortionary capital taxation even if lump‐sum taxation is available. In addition, this insurance effect counteracts the tendency toward too low tax rates on capital arising from tax competition, and possibly improves the efficiency of tax competition.  相似文献   
62.
This paper uses a tractable macroeconomic model with idiosyncratic human capital risk and incomplete markets to analyze the growth and welfare effects of business cycles. The analysis is based on the assumption that the elimination of business cycles eliminates the variation in idiosyncratic risk. The paper shows that a reduction in the variation in idiosyncratic risk decreases the ratio of physical to human capital and increases the total investment return and welfare. If the degree of risk aversion is less than or equal to one, then economic growth is enhanced. This paper also provides a quantitative assessment of the macroeconomic effects of business cycles based on a calibrated version of the model. Even for relatively small degrees of risk aversion (around one) the model implies that the elimination of business cycles has substantial effects on investment in physical and human capital, economic growth, and welfare.  相似文献   
63.
Entry deterrence and innovation in durable-goods monopoly   总被引:1,自引:0,他引:1  
This paper investigates the efficiency of innovation investments in a durable-goods monopoly when a potential entrant threatens to innovate as well. We show that the durability of the good endows the monopolist with the power to discourage rival innovation since current sales alter the demand for a new generation of the good. The equilibrium is therefore determined not only by the incentive for intertemporal price discrimination in durable-goods monopoly, but also by the incumbent's concern for maintaining the technological leadership. We demonstrate that entry deterrence followed by no innovation always implies underinvestment in innovation.  相似文献   
64.
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   

65.
An increasing number of large and multinational organizations are moving to shared services models in delivering the human resource function. It is commonly believed that the adoption of an HR shared services model can transform the role of HR by enabling the HR function to be more strategic at the corporate level and more cost‐effective at the operational level. However, few academic studies have been carried out to investigate challenges to implementing an HR services center successfully and the impact of adopting an HR shared services model on different groups of employees. Through a case study of a multinational corporation, this article reveals that there remains a significant gap between literature espousing the efficacy and utility of HR shared services and the extent to which the adoption of such a model is successful. The financial and emotional cost of moving to a shared services model can outweigh the tangible cost savings predicted by firms. The idea of separating the HR function into strategic, operational, and administrative components may prove to be too simplistic, although it underpins the initiative of HR shared services. © 2006 Wiley Periodicals, Inc.  相似文献   
66.
We investigate why real estate investment trusts (REITs) still engage in open-market repurchases given the unique 95 percent payout requirement. We provide evidence that the motivations for REITs to repurchase stocks are different from those of unregulated firms found by the existing literature. Instead of using funds from operations, REITs appear to finance stock repurchases by issuing new debt and/or selling assets and investments. Unlike ordinary corporations, REITs stock repurchases are not motivated by cash distribution, capital structure, and undervalued equity. However, REITs are more likely to buy back stocks when employees own a higher level of stock options. Also, we find that REITs are more likely to buy back stocks when they have a higher institutional ownership and/or inside ownership.  相似文献   
67.
This paper considers a linear triangular simultaneous equations model with conditional quantile restrictions. The paper adjusts for endogeneity by adopting a control function approach and presents a simple two-step estimator that exploits the partially linear structure of the model. The first step consists of estimation of the residuals of the reduced-form equation for the endogenous explanatory variable. The second step is series estimation of the primary equation with the reduced-form residual included nonparametrically as an additional explanatory variable. This paper imposes no functional form restrictions on the stochastic relationship between the reduced-form residual and the disturbance term in the primary equation conditional on observable explanatory variables. The paper presents regularity conditions for consistency and asymptotic normality of the two-step estimator. In addition, the paper provides some discussions on related estimation methods in the literature.  相似文献   
68.
With the development of an MCMC algorithm, Bayesian model selection for the p 2 model for directed graphs has become possible. This paper presents an empirical exploration in using approximate Bayes factors for model selection. For a social network of Dutch secondary school pupils from different ethnic backgrounds it is investigated whether pupils report that they receive more emotional support from within their own ethnic group. Approximated Bayes factors seem to work, but considerable margins of error have to be reckoned with.  相似文献   
69.
For a balanced two-way mixed model, the maximum likelihood (ML) and restricted ML (REML) estimators of the variance components were obtained and compared under the non-negativity requirements of the variance components by L ee and K apadia (1984). In this note, for a mixed (random blocks) incomplete block model, explicit forms for the REML estimators of variance components are obtained. They are always non-negative and have smaller mean squared error (MSE) than the analysis of variance (AOV) estimators. The asymptotic sampling variances of the maximum likelihood (ML) estimators and the REML estimators are compared and the balanced incomplete block design (BIBD) is considered as a special case. The ML estimators are shown to have smaller asymptotic variances than the REML estimators, but a numerical result in the randomized complete block design (RCBD) demonstrated that the performances of the REML and ML estimators are not much different in the MSE sense.  相似文献   
70.
Performance lies arise both from individual and from situational causes, but in this article, the attention is on situational causes. These are generally triggered by loyalty to the coalition, which is expressed through the continued use of performance lies. Because performance lies help create a boundary around the coalition that insulates its activities from top management, performance lies enable members of the coalition to exercise a greater degree of internal control. Naturally, such lies are dysfunctional, resulting in the avoidance of difficult issues and problems and compromising the organization's ability to adapt to a changing environment based on accurate information.  相似文献   
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