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151.
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
152.
153.
Charles M. Vance Ellen A. Ensher Frederica M. Hendricks Claudia Harris 《Employee Responsibilities and Rights Journal》2004,16(3):135-147
The purpose of this study was to explore evidence of gender-based vicarious sensitivity to disempowering behavior in organizations, expanding the concept of hostile working environment beyond the context of sexual harassment. Male and female graduate and undergraduate students viewed 10 video segments of Anita Hill's interview by U.S. senators during the October 1991 confirmation hearings of Supreme Court Justice Nominee, Clarence Thomas. Although no significant relationship was found between the personal attributes of age and ethnicity to perceptions of disempowering behavior, female participants reported seeing significantly more offensive behavior in the video segments than did male participants. The results are discussed in terms of greater female sensitivity to common forms of disempowering behavior in organizations, and having a disparate negative impact and systematically placing women at a disadvantage in today's workforce. 相似文献
154.
Robustness issues in multilevel regression analysis 总被引:8,自引:0,他引:8
A multilevel problem concerns a population with a hierarchical structure. A sample from such a population can be described as a multistage sample. First, a sample of higher level units is drawn (e.g. schools or organizations), and next a sample of the sub‐units from the available units (e.g. pupils in schools or employees in organizations). In such samples, the individual observations are in general not completely independent. Multilevel analysis software accounts for this dependence and in recent years these programs have been widely accepted. Two problems that occur in the practice of multilevel modeling will be discussed. The first problem is the choice of the sample sizes at the different levels. What are sufficient sample sizes for accurate estimation? The second problem is the normality assumption of the level‐2 error distribution. When one wants to conduct tests of significance, the errors need to be normally distributed. What happens when this is not the case? In this paper, simulation studies are used to answer both questions. With respect to the first question, the results show that a small sample size at level two (meaning a sample of 50 or less) leads to biased estimates of the second‐level standard errors. The answer to the second question is that only the standard errors for the random effects at the second level are highly inaccurate if the distributional assumptions concerning the level‐2 errors are not fulfilled. Robust standard errors turn out to be more reliable than the asymptotic standard errors based on maximum likelihood. 相似文献
155.
In this paper characterizations of negative multinomial distributions based on conditional distributions have been studied. 相似文献
156.
Improving productive efficiency is an increasingly important determinant of the future of the swine industry in Hawaii. This paper examines the productive efficiency of a sample of swine producers in Hawaii by estimating a stochastic frontier production function and the constant returns to scale (CRS) and variable returns to scale (VRS) output-oriented DEA models. The technical efficiency estimates obtained from the two frontier techniques are compared. The scale properties are also examined under the two approaches. The industry's potential for increasing production through improved efficiency is also discussed. 相似文献
157.
158.
Many textbooks on project management present illustrations concerning the relative size of project attributes during different project phases. The derived models all have attributes in common, such as uncertainty, significance of decisions, and degree of freedom to maneuver, that are typically high in the beginning of the project and low in the end. At the same time, variables such as the accumulated cost and available information begin at low levels and end up at a high level at the end of the project. Based on empirical data from projects, this paper illustrates and quantifies one of these attributes, the freedom to maneuver, in different project phases. 相似文献
159.
This paper focuses on: (1) how a select set of financial and economic factors could set the path for interest rates and foreign exchange rates, and (2) whether the resultant realized interest and exchange rates would be in harmony or in disarray. Using post-euro data for the EU and the US, an array of monetary rules is examined. In particular, the paper investigates whether the original and the extended Taylor rules provide an explanation of the dynamics of the EU monetary system since the inception of the euro. Our findings indicate that the EU and the US monetary responses are not the same and that exchange rates play a significant role. 相似文献
160.
汽车制造商和零件供应商可以节省巨大开支,但前提是双方要更为紧密地合作在一起麦肯锡的研究表明,北美汽车业每年在产品开发和组装过程中由于汽车生产商与供应商缺乏良好的计划和协调不当,造成了超过100亿美元的浪费。事实上.这只是较为保守的估算。因为我们的研究仅涵盖了供应商发生的成本,如:附加设计、生产工具最后改型和零件自身的附加成本。这还不包括因设计问题生产商需额外支付的改型费用、生产问题引发的车辆最终成本的增加或质保支出。这几项每年给汽车行业带来的浪费约为120亿美元。 相似文献