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871.
In comparing several regressions E(yij) =αi + βixij i = 1, 2, ..., k, j = 1,2, ..., ni, researchers are generally interested in the following five problems: whether they have (1) equal slope, (2) equal intercept, (3) coincidence, (4) common intersection on X-axis, and (5) common intersection on (X,Y) - plane. Problems (1) - (3) can be put into the framework of the general linear hypothesis and the F-test can be used. However, problems (4) and (5) cannot be put into the general linear hypothesis because they are ratios of parameters. Hence, in this paper we consider the generalized likelihood ratio test for hypothesis testing. An application to an enzyme kinetics problem in Aniline Metabolism is demonstrated 相似文献
872.
873.
With the high number of homeless, there is a critical need for rapid and accurate assessment of quality of life to assess
program outcomes. The World Health Organization’s WHOQOL-100 has demonstrated promise in accurately assessing quality-of-life
in this population. However, its length may make large scale use impractical for working with a homeless population. The World
Health Organization Quality of Life—Brief version (WHOQOL-BREF), though providing a shorter instrument and being, theoretically,
more manageable has not been evaluated for use with homeless individuals. This study evaluated the psychometric properties
of the WHOQOL-BREF in 389 homeless veterans. Adequate internal consistency for all domains was found and validity for each
domain was supported using the Personality Assessment Inventory. The WHOQOL-BREF provides a reliable, valid, and brief assessment
of quality-of-life. Due to the length of the instrument and the domains covered, it could have great utility in the assessment
of homeless populations with multiple problem domains. 相似文献
874.
875.
John Bongaarts Susan Greenhalgh Geoffrey McNicoll Michael P. Todaro Etienne van de Walk Zachary Zimmer 《Population and development review》2001,27(3):608-617
Books reviewed in this article: Gay Becker, The Elusive Embryo: How Women and Men Approach New Reproductive Technologies Theodore Caplow, Louis Hicks, and Ben J. Wattenberg, The First Measured Century: An Illustrated Guide to Trends in America, 1900–2000 Stephen Moore and Julian L. Simon, It's Getting Better All the Time: 100 Greatest Trends of the Last 100 Years Elisabeth Croll, Endangered Daughters: Discrimination and Development in Asia Barbara Entwisle and Gail E. Henderson (Eds.), Re‐Drawing Boundaries: Work, Households, and Gender in China David T. Graham and Nana K. Poku (Eds.), Migration, Globalisation and Human Security Paul Harrison and Fred Pearce, AAAS Atlas of Population and Environment Russell King, Paolo De Mas, and Jan Mansvelt Beck (Eds.), Geography, Environment and Development in the Mediterranean Michael T. Klare, Resource Wars: The New Landscape of Global Conflict Korea Institute for Health and Social Affairs and United Nations Population Fund, Low Fertility and Policy Responses to Issues of Ageing and Welfare National Assessment Synthesis Team, Climate Change Impacts on the United States: The Potential Consequences of Climate Variability and Change. Report for the US Global Change Research Program Jacques Vaixin and Thérèse Locoh (Eds.), Population et développement en Tunisie: La métamorphose 相似文献
876.
The paper explores the outcomes of permanent family placement for children of minority ethnic origin, using a sample of 254 placements drawn, in the main, from a cohort of 1165 British children placed between 1980 and 1985. Statistical techniques are used to explore the relationship between 'success' (defined, for the purposes of this paper, as the placement not known to have broken down) and a range of variables, including the characteristics of the child, the birth parents and the adoptive parents, and the type of placement. In most respects, the findings are consistent with those of similar studies. Age at placement is found to have an important effect, with success least likely for children placed in the middle age range. Lack of problem behaviours in the children at the time of placement is also found to be associated with success. Variables which are found to have no effect on the probability of success include ethnic origin of the child, whether it is an adoptive or permanent foster placement, and whether contact with birth parents continued after placement. There was an interesting gender effect in that boys did better in 'transracial' than in 'matched' placements, but the opposite was the case for girls. 相似文献
877.
It has become a commonplace to argue that in the face of a discredited Marxism, socialism must find an alternative basis for a renewed project. This article investigates two of these claims by Gerald Cohen and Bob Fitch. It does so with particular reference to the attempt by these authors to re-invoke, both wittingly and unwittingly, David Ricardo, John Stuart Mill, Henry George, and Auguste Comte among others as the source of a renewed left project. It takes as its special concern the way in which the supposed need to revivify "industry" in the late twentieth century parallels the often voiced need to revivify "agriculture" in the late nineteenth century as a means of staving off "underdevelopment." 相似文献
878.
P D Kurtz 《Child welfare》1979,58(3):165-176
Early identification of handicapping conditions in children greatly enhances the possibility of treatment that may limit malfunctioning. Social work has responsibility and an opportunity to become more active in early identification. 相似文献
879.
本文建立了火焰原子吸收光谱法测定硫酸中铁和锌的方法。确定了最佳仪器工作条件和样品处理方法。在选择好的实验条件下,测定铁的特征浓度为0.014μg/mL/1%吸收;测定锌的特征浓度为0.002μg/mL/1%吸收。回收率分别为铁98.8%—103.4%,锌92.5%—98.6%。 相似文献
880.
S. P. Brooks 《Statistics and Computing》1998,8(3):267-274
Yu (1995) provides a novel convergence diagnostic for Markov chain Monte Carlo (MCMC) which provides a qualitative measure of mixing for Markov chains via a cusum path plot for univariate parameters of interest. The method is based upon the output of a single replication of an MCMC sampler and is therefore widely applicable and simple to use. One criticism of the method is that it is subjective in its interpretation, since it is based upon a graphical comparison of two cusum path plots. In this paper, we develop a quantitative measure of smoothness which we can associate with any given cusum path, and show how we can use this measure to obtain a quantitative measure of mixing. In particular, we derive the large sample distribution of this smoothness measure, so that objective inference is possible. In addition, we show how this quantitative measure may also be used to provide an estimate of the burn-in length for any given sampler. We discuss the utility of this quantitative approach, and highlight a problem which may occur if the chain is able to remain in any one state for some period of time. We provide a more general implementation of the method to overcome the problem in such cases. 相似文献