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921.
ABSTRACT In most treatments of nonparametric regression, it is assumed that the marginal density of the explanatory variables is strictly bounded away from zero and infinity. This note investigates the pointwise asymptotics for nonparametric regression when this assumption fails, that is, the marginal density of the explanatory variable has either an isolated zero or a pole at the point of interest. 相似文献
922.
M. Pithuncharurnlap K.E. Basford W.T. Federer 《Australian & New Zealand Journal of Statistics》1993,35(3):263-270
In field experiments involving a large number of experimental plots, a neighbour analysis can be used to control environmental variation by estimating the trend within blocks. The effect of interplot competition is another important source of variation which has an influence on the estimation of treatment contrasts. To reduce the effect of the variation from these sources and to improve the precision of comparison between treatments, a spatial model is proposed for incorporating both trend effect and interplot competition. It is a modification to the residual maximum likelihood neighbour analysis of Gleeson & Cullis (1987) using the two neighbouring treatment effects to estimate interplot competition. A real example is used to illustrate this methodology. The results indicate that the extended model gives no appreciable difference in standard error of mean differences compared with the model taking into account the trend effect only. However, the rankings of estimated treatment means do differ. More research using both real and simulated data is required before such models that incorporate trend and competition effects can be confidently recommended. 相似文献
923.
Dr. Joseph M. Chandy Ph.D. Dr. Robert W. Blum M.D. Ph.D. M.P.H. Dr. Michael D. Resnick Ph.D. 《Child and Adolescent Social Work Journal》1996,13(5):411-432
This study examined the school performance, suicidal involvement, disordered eating behaviors, pregnancy risk and chemical use of teenagers with a history of sexual abuse or parental alcohol misuse and found that they had higher rates of these adverse outcomes than among a comparison group of teenagers without such background risk factors. Adolescents with dual-risk background reported higher levels of suicide risk, disordered eating, sexual behaviors and chemical abuse than teenagers with only one background risk factor. Among index group members, protective factors against these adverse outcomes included a high degree of religiosity and the ability to discuss problems with family or friends. Risk factors that increased the likelihood of adverse outcomes included depression, perceived substance use in school and worries about family financial security.The first author was supported in the preparation of this article by a grant from the Lois and Samuel Silberman Fund of New York. 相似文献
924.
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926.
Alan B. Franklin David R. Anderson Kenneth P. Burnham 《Journal of applied statistics》2002,29(1-4):267-287
We obtained banding and recovery data from the Bird Banding Laboratory (operated by the Biological Resources Division of the US Geological Survey) for adults from 129 avian species that had been continuously banded for > 24 years. Data were partitioned by gender, banding period (winter versus summer), and by states/provinces. Data sets were initially screened for adequacy based on specific criteria (e.g. minimum sample sizes). Fifty-nine data sets (11 waterfowl species, the Mourning Dove and Common Grackle) met our criteria of adequacy for further analysis. We estimated annual survival probabilities using the Brownie et al. recovery model {St, ft} in program MARK. Trends in annual survival and temporal process variation were estimated using random effects models based on shrinkage estimators. Waterfowl species had relatively little variation in annual survival probabilities (mean CV = 8.7% and 10% for males and females, respectively). The limited data for other species suggested similar low temporal variation for males, but higher temporal variation for females (CV = 40%). Evidence for long-term trends varied by species, banding period and sex, with no obvious spatial patterns for either positive or negative trends in survival probabilities. An exception was Mourning Doves banded in Illinois/Missouri and Arizona/New Mexico where both males (slope = -0.0122, se = 0.0019 and females (slope = -0.0109 to -0.0128, se = 0.0018 -0.0032) exhibited declining trends in survival probabilities. We believe our approach has application for large-scale monitoring. However, meaningful banding and recovery data for species other than waterfowl is very limited in North America. 相似文献
927.
Matthew W. Finkin 《Journal of Labor Research》2005,26(4):711-723
Bruce Kobayashi and Larry Ribstein apply the “theory of the firm” to worker privacy with specific application to the employer’s
ability to monitor employee performance and behavior. They take the theory to drive toward a much reduced role for law in
favor of regulation by contract. This essay unpacks their theory. It faults the theory for its failure to come to grips with
the possibility of monopsony in the labor market, its failure to appreciate the “public goods” nature of privacy policies
and the related assumption that the employer’s ability to adopt and apply privacyinvasive policies is invariably a product
of a consensual armslength bargain.
This essay is revised and expanded from the author’s Introduction to the 2003 Supplement to Matthew Finkin, Privacy in Employment Law (2d ed. 2003) 2003 Supplement. 相似文献
928.
929.
采用湿化学方法制备了Co掺杂的二氧化锡纳米粉(Sn1-xCoxO2),经研究发现,Co以离子形式存在,而不是以单质形式存在,样品中除了金红石型的SnO2相之外,没有发现其他杂质的相,随着Co掺杂含量的增加,晶粒尺寸减小,光吸收谱红移,禁带宽度线性下降。钴离子磁矩随掺杂含量的增加而减小,这可能是由于占据晶格上近邻阳离子位置的磁性离子数目增加使磁性离子成反铁磁性排列的结果。 相似文献
930.
Robert W. Dimand 《International Review of Sociology》2004,14(3):461-470
Irving Fisher's debt-deflation theory of great depressions, first published in 1932 and 1933, was invoked by Hyman Minsky and James Tobin as a crucial precursor of their theories of macroeconomic financial instability. This paper argues that Wesley Mitchell was right to perceive a close intellectual affinity between Fisher's debt-deflation theory and Thorstein Veblen's Theory of Business Enterprise (1904), and that this affinity also exists between Veblen (1904) and the analyses of Minsky and Tobin. 相似文献