排序方式: 共有47条查询结果,搜索用时 15 毫秒
41.
Alan Dorfman 《统计学通讯:理论与方法》2013,42(10):3521-3535
For heteroscedastic simple linear regression when the variances are proportional to a power of the mean of the response variable, Miller (1986) recommends the following procedure: do a weighted least squares regression with the weights (empirical weights) estimated by the inverse of the appropriate power of the response variable. The practical appeal of this approach is its simplicity. In this article some of the consequences of this simple procedure are considered. Specifically, the effect of this procedure on the bias of the point estimators of the regression coefficients and on the coverage probabilities of their corresponding confidence intervals is examined. It is found that the performance of the process of employing empirical weights in a weighted least squares regression depends on : (1) the particular regression parameter (slope or intercept) of interest, (2) the appropriate power of the mean of the response variable involved, and (3) the amount of variation in the data about the true regression line. 相似文献
42.
《统计学通讯:理论与方法》2013,42(7):1533-1541
ABSTRACT The systematic sampling (SYS) design (Madow and Madow, 1944) is widely used by statistical offices due to its simplicity and efficiency (e.g., Iachan, 1982). But it suffers from a serious defect, namely, that it is impossible to unbiasedly estimate the sampling variance (Iachan, 1982) and usual variance estimators (Yates and Grundy, 1953) are inadequate and can overestimate the variance significantly (Särndal et al., 1992). We propose a novel variance estimator which is less biased and that can be implemented with any given population order. We will justify this estimator theoretically and with a Monte Carlo simulation study. 相似文献
43.
Global Englishes, Rip Slyme, and performativity 总被引:1,自引:0,他引:1
Alastair Pennycook 《Journal of Sociolinguistics》2003,7(4):513-533
In this article I suggest that while recent sociolinguistic work focusing on crossing, styling the Other or language boundaries is raising significant questions concerning how we relate language, identity and popular culture, these insights have largely passed by the sociolinguistics of world Englishes. This latter work is still caught between arguments about homogeneity and heterogeneity, between arguments based on liberal accommodationism, linguistic imperialism or linguistic hybridity that do not allow for sufficiently complex understandings of what is currently happening with global Englishes. Focusing particularly on rap music, I suggest that we need, at the very least, a critical understanding of globalization, a focus on popular cultural flows, and a way of taking up performance and performativity in relationship to identity and culture. 相似文献
44.
Ruth Marcus 《Australian & New Zealand Journal of Statistics》1981,23(2):214-223
The one-way ANOVA model is considered. The variances are assumed to be either equal but unknown or unequal and unknown. Two-stage procedures for generating simultaneous confidence intervals (SCI) for the class of monotone contrasts of the means are presented. The intervals are of fixed length and independent of the unknown variances. 相似文献
45.
利用2010年广东家庭追踪调查城镇部分数据,研究转型期城镇家庭住房困难状况,结果发现:城镇家庭收入与住房困难成“倒U”关系,其他因素如家庭规模、户籍分割及高房价背景均与住房困难存在明显关系,但住户特征与住房困难的关系较弱。显然,理解转型期城市住房困难现象不能仅从市场的收入逻辑进行解释,住房市场嵌入在各种制度因素之中,旧的分配制度与新的市场因素均会左右城镇家庭的住房状况,住房困难是家庭特征、市场环境及国家力量共同作用的结果。 相似文献
46.
从认知社会语言学的世界英语变体研究看中国英语研究 总被引:1,自引:0,他引:1
周红英 《南京理工大学学报(社会科学版)》2010,23(4):90-96
认知社会语言学从文化认知和社会语言系统的浮现性、动态性和开放性提出认知和语言是复合适应系统,并通过世界英语变体在特定社会文化语境下的语义变异及其背后的的文化认知理据论证了英语变体对特定文化认知的适应性和创新性。世界英语变体的认知社会语言学视角和方法对推进和深化我国目前的中国英语研究具有重要的启示,对中国英语研究、世界英语变体研究乃至英语全球化的认识都有重要的意义。 相似文献
47.
Stephen Evans 《Journal of Sociolinguistics》2014,18(5):571-603
Schneider's ( 2007 ) ground‐breaking Dynamic Model is widely regarded as the most comprehensive and coherent theory to account for the evolution of postcolonial Englishes, but has yet to be validated by evidence from detailed historical research. This article seeks to bridge this gap by presenting an empirically‐grounded case study of the evolution of Hong Kong English based on the four parameters in Schneider's ( 2007 ) framework, viz. sociopolitical background, identity constructions, sociolinguistic conditions, and linguistic effects. Whereas previous applications of the framework have relied on synchronic data, this study draws on sets of primary data spanning 170 years. These diachronic datasets make it possible to demarcate distinct phases in the use of English in society and the evolution of its community of users. The study casts doubt on the accuracy of Schneider's account of the evolution of Hong Kong English and, more generally, the applicability of the Dynamic Model to Outer Circle contexts. 相似文献