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71.
Abstract

In this paper we find the maximum likelihood estimates (MLEs) of hazard rate and mean residual life functions (MRLF) of Pareto distribution, their asymptotic non degenerate distribution, exact distribution and moments. We also discuss the uniformly minimum variance unbiased estimate (UMVUE) of hazard rate function and MRLF. Finally, two numerical examples with simulated data and real data set, are presented to illustrate the proposed estimates.  相似文献   
72.
Abstract

Objective: To examine the efficacy of a self-affirmation task in deterring college alcohol misuse and the importance of preexisting beliefs in predicting subsequent behavior change. Participants: Heavy-drinking undergraduates (N = 110) participated during the 2011–2012 academic year. Methods: Participants were randomized to complete an affirmation or control task before reading an alcohol risk message. Alcohol-related beliefs and behaviors were assessed. Participants completed a 2-week online follow-up assessing alcohol-related behaviors. Results: Both groups reported increased perceived problem importance, but neither group displayed changes in personal risk. Follow-up assessment revealed similar, significant declines in peak consumption in both groups, with no significant between-group differences. Preexisting beliefs accounted for 5% to 10% of variance in drinking outcomes. Conclusions: An affirmation task does not seem to decrease defensive processing or alter high-risk drinking behaviors among college students and should not be utilized in lieu of more effective strategies.  相似文献   
73.
This paper introduces trade adjustment considerations as active determinants of trade policy. Using novel U.S. data sets, I show that, despite their small monetary value, trade‐induced unemployment and trade‐adjustment costs can incite an incumbent politician to grant protection to an unorganized industry, even in the presence of political pressure by organized sectors. This finding complements the theoretical predictions from Grossman and Helpman (American Economic Review, 84, 1994, 833–50) who argue that the government should protect organized industries but should subsidize imports in unorganized sectors. (JEL D73, F13, F14, F16, J68)  相似文献   
74.
75.
Objective. Ex‐felon voter turnout was estimated for the first time using government records rather than statistical models. Statistical models have estimated that 25–35 percent of eligible ex‐felons would vote in federal elections. Methods. Six‐hundred‐sixty recently released ex‐felons in Erie County, NY, who would have been legally eligible to register and vote in 2004 or 2005, were compared with data from the Erie County Board of Elections to determine whether they registered and voted in either 2004 or 2005. Results. Five percent this population of ex‐felons voted in either 2004 or 2005. Conclusions. Single‐digit turnout among ex‐felons raises questions about the assumptions underlying statistical estimates, and it also suggests that elections would have to be very close for ex‐felons to have an impact on the results.  相似文献   
76.
We examine the effect of a hospital's objective (i.e., non‐profit vs. for‐profit) in hospital markets for elective care. Using game‐theoretic analysis and queueing models to capture the operational performance of hospitals, we compare the equilibrium behavior of three market settings in terms of such criteria as waiting times and patient costs from waiting and hospital payments. In the first setting, a monopoly, patients are served exclusively by a single non‐profit hospital; in the second, a homogeneous duopoly, patients are served by two competing non‐profit hospitals. In our third setting, a heterogeneous duopoly, the market is served by one non‐profit hospital and one for‐profit hospital. A non‐profit hospital provides free care to patients, although they may have to wait; for‐profit hospitals charge a fee to provide care with minimal waiting. A comparison between the monopolistic and each of the duopolistic settings reveals that the introduction of competition can hamper a hospital's ability to attain economies of scale and can also increase waiting times. Moreover, the presence of a for‐profit sector may be desirable only when the hospital market is sufficiently competitive. A comparison across the duopolistic settings indicates that the choice between homogeneous and heterogeneous competition depends on the patients' willingness to wait before receiving care and the reimbursement level of the non‐profit sector. When the public funder is not financially constrained, the presence of a for‐profit sector may allow the funder to lower both the financial costs of providing coverage and the total costs to patients. Finally, our analysis suggests that the public funder should exercise caution when using policy tools that support the for‐profit sector—for example, patient subsidies—because such tools may increase patient costs in the long run; it might be preferable to raise the non‐profit sector's level of reimbursement.  相似文献   
77.
This study uses a service operations management (SOM) strategy lens to investigate chain store retailers' strategic design responsiveness (SDR)—a term that captures the degree to which retailers dynamically coordinate investments in human and structural capital with the complexity of their service and product offerings. Labor force and physical capital are respectively used as proxies for investments in human capital and structural capital, whereas gross margins are proxies for product/service offering complexity. Consequently, SDR broadly reflects three salient complementary choices of SOM design strategy. We test the effects of “brick and mortar” chain store retailers' SDR on current and future firm performance using publically available panel data collected from Compustat and the University of Michigan American Customer Satisfaction Index databases for the period 1996–2011. We find that retailers that fail to keep pace with investments in both structural and human capital exhibit short‐term financial benefits, but have worse ongoing operational performance. These findings corroborate the importance of managers strategically maintaining the complementarity of design‐related choices for improving and maintaining business performance.  相似文献   
78.
Popular clothing retailer Abercrombie and Fitch (A&F) is well‐known for hiring attractive store sales clerks. While the economic benefits of this hiring practice for the company are undeniable, many commentators contend that it constitutes wrongful discrimination against unattractive job seekers. In this article, I explore the ethics of A&F‐style lookism and challenge two common perspectives on this issue. I argue that on one hand, looks‐based hiring cannot be defended based on its economic benefits alone, as race‐based hiring also can be profitable in some circumstances. At the same time, I reject arguments that looks‐based hiring is not “job relevant” given its economic impact in many contexts. Through a comparison between race‐ and looks‐based hiring, I conclude that at least for businesses that are relevantly similar to A&F—firms for which lookism produces clear economic benefits—looks‐based hiring is permissible.  相似文献   
79.
This paper deals with a longitudinal semi‐parametric regression model in a generalised linear model setup for repeated count data collected from a large number of independent individuals. To accommodate the longitudinal correlations, we consider a dynamic model for repeated counts which has decaying auto‐correlations as the time lag increases between the repeated responses. The semi‐parametric regression function involved in the model contains a specified regression function in some suitable time‐dependent covariates and a non‐parametric function in some other time‐dependent covariates. As far as the inference is concerned, because the non‐parametric function is of secondary interest, we estimate this function consistently using the independence assumption‐based well‐known quasi‐likelihood approach. Next, the proposed longitudinal correlation structure and the estimate of the non‐parametric function are used to develop a semi‐parametric generalised quasi‐likelihood approach for consistent and efficient estimation of the regression effects in the parametric regression function. The finite sample performance of the proposed estimation approach is examined through an intensive simulation study based on both large and small samples. Both balanced and unbalanced cluster sizes are incorporated in the simulation study. The asymptotic performances of the estimators are given. The estimation methodology is illustrated by reanalysing the well‐known health care utilisation data consisting of counts of yearly visits to a physician by 180 individuals for four years and several important primary and secondary covariates.  相似文献   
80.
We propose an influence diagnostic methodology for linear regression models with stochastic restrictions and errors following elliptically contoured distributions. We study how a perturbation may impact on the mixed estimation procedure of parameters in the model. Normal curvatures and slopes for assessing influence under usual schemes are derived, including perturbations of case-weight, response variable, and explanatory variable. Simulations are conducted to evaluate the performance of the proposed methodology. An example with real-world economy data is presented as an illustration.  相似文献   
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