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191.
192.
J W M Cameron 《Development Southern Africa》1986,3(2):265-280
Urban development in Southern Africa has reflected western values and standards relating to health, safety, order, amenity, convenience and general welfare, and only incidentally to efficiency and economy. This article describes a project which relates to different value systems, and has different objectives. It highlights the imperatives for change, namely population growth, urbanisation and declining per capita GDP growth. In this milieu, the objective of affordability becomes paramount Standards are related to resources and are based on consultation with the developing community.
The article describes four key elements in the ‘Guidelines for Services and amenities’ being prepared by the CSIR for the Department of Development Aid, namely stormwater management, public transport, road layout and development density. It concludes by cautioning against development policies which deny or misunderstand the economic forces which drive the process of urbanisation. 相似文献
193.
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
194.
195.
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
196.
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
197.
In this paper characterizations of negative multinomial distributions based on conditional distributions have been studied. 相似文献
198.
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
199.
200.
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