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991.
In this paper, we discuss the properties of preliminary test estimators (PTE) of the parameters of simple linear model with measurement error (ME model) when the slope of the linear model is suspected to be zero. Expressions of the bias, MSE and efficiencies are obtained under conditional as well as unconditional situations with known reliability coefficient. Conditional model results are compared to the standard model without measurement error. We also provide the unconditional model analysis in finite samples. Asymptotic theory under local alternatives is developed when the variance of measurement error or the ratio of the variance of the model error relative to the variance of the measurement error is known. Asymptotic expressions of bias and MSE of the estimators along with their efficiencies are obtained. In every case, it is shown that the measurement error tend to increase the variability of the estimators compared to the estimators without measurement error. Graphs and tables are provided to see these results and to determine optimum level of significance for minimum guaranteed efficiency. Received October 2001 RID="*" ID="*"  A. K. Md. E. Saleh is a Distinguished Research Professor and H. M. Kim is a Ph.D. candidate in the School of Mathematics and Statistics, Carleton University, Ottawa. Acknowledgment. The authors gratefully acknowledge the constructive suggestion of the referees to improve the paper. The research is supported by NSERC grant A3088.  相似文献   
992.
Rimar JM  Diers D 《Nursing economic$》2006,24(6):298-307, 279
Nursing unit volume-outcome relationships exist for patients assigned selected DRGs. This finding suggests that, in some cases, aggregating inpatients with similar clinical conditions may result in lower cost of care, shorter length of stay, and fewer hospital deaths.  相似文献   
993.
近年来,世界各国民主化的趋势使得学者们必须面对两个具有潜在矛盾的目标:其一是建立一个能涵盖各个国家不同经验、具有多样性的民主概念;其二是在不扩大概念的基础上扩大对这一大类案例的分析。本文认为这种双重挑战导致了概念创新的加速,产生了几百种民主的亚类型———也就是“带形容词”的民主。本文对出现的三种重要创新类型的优势和弱点进行了探讨,这三种类型是:对民主定义的“精确化”;对与民主相关联的大概念进行转化;以及建立不同的亚类型。鉴于这些重新定义民主概念的策略所产生的含义具有复杂的结构,我们显得老生常谈式的结论其实具有新的紧迫含义:学者们必须通过对他们所使用的民主概念进行清楚的定义和说明来为自己的研究定位。  相似文献   
994.

University business incubators (UBIs) are an important part of the ecosystem that supports entrepreneurial activities and economic development. Extant research has focused on examining UBI activities at a single point in time, but there is a paucity of theoretical and empirical work aimed at understanding the forces that explain why and how UBIs change over time. This is an important gap because establishing a university business incubator does not assure its development and growth. We address this issue by drawing upon the Fisher et al. Academy of Management Review, 41(3), 383-409 (2016) Identity-Legitimacy-Life Cycle model to explain how the pursuit of resources and organizational legitimacy shapes the development of UBIs along key strategic and operational dimensions, which has implications for performance evaluation over time. We illustrate with a case study about the creation and evolution of the DMZ, a leading UBI at Ryerson University in Canada. This case provides new insights about the dynamics of UBIs and their relationships with the entrepreneurial ecosystems in which they are embedded. Implications for future research, management practice, and public policy are discussed.

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Despite the importance of good collaborative relationships in interorganisational projects, clients and contractors often develop adversarial relationships due to perceptual distance about key project issues. In this case study research, we investigated how perceptual distance emerges and changes over time, and how the collaborative relationship between client and contractor develops alongside these dynamics. In this exploration, we built upon agency theory and stewardship theory as complementary perspectives for understanding client-contractor collaborative relationships. We gathered quantitative and qualitative data in two projects, conducting three assessments in about one year. We found that perceptual distance increased and decreased over time, and that a reduction was typically associated with the collaborative relationship being characterized by stewardship rather than agency. These findings suggest that a regular assessment and evaluation of partners’ perceptions of critical project issues is warranted to timely detect and counteract perceptual distance. Moreover, partners would best adopt a stewardship orientation to reduce perceptual distance, although this may take considerable effort given the distributive nature of many pre-project negotiations.  相似文献   
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The National Basketball Association contracting rules provide plausibly exogenous variation in career concerns near contract end. We use this setting to study how individual career concerns affect risk‐taking behavior and can sabotage team performance. Using the frequency and duration of player injuries from 1991 to 2013 we measure individual risk‐taking behavior. We find that the average player's likelihood of missing a game due to injury falls by 0.06 percentage points (or over 100% relative to the mean injury rate) in the final 3 months of his contract, and when missing games due to injury is unavoidable, his recovery time drops by 22 days. However, “elite” players with virtually no career concerns actually miss more games due to injury. Finally, we find that elite players missing too many games and “average” players playing before healthy, combine to hurt team performance. For each additional player in the last 3 months on contract, the win probability for that team falls by over 2.6%.  相似文献   
1000.
This article analyzes the Supreme Court's decision in Bragdon v. Abbott to determine whether the Court's reading of ADA necessarily leads to the conclusion that a group health plan's or insurer's exclusion or limitation of coverage with respect to infertility is prohibited by ADA. The authors conclude that it may be advisable for plans to perform at least minimal actuarial calculations with respect to the current or anticipated costs of covering infertility treatments prior to adopting any exclusions or limitations of coverage.  相似文献   
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