Estimation in an empirical bayes model for longitudinal and cross‐sectionally clustered binary data

Some studies generate data that can be grouped into clusters in more than one way. Consider for instance a smoking prevention study in which responses on smoking status are collected over several years in a cohort of students from a number of different schools. This yields longitudinal data, also cross‐sectionaliy clustered in schools. The authors present a model for analyzing binary data of this type, combining generalized estimating equations and estimation of random effects to address the longitudinal and cross‐sectional dependence, respectively. The estimation procedure for this model is discussed, as are the results of a simulation study used to investigate the properties of its estimates. An illustration using data from a smoking prevention trial is given.     

The dynamics of negation: identity formation among Palestinian Arab college students inside the green line

How does granting certificates of ‘business clean of Arab workers’ to owners of shops, stores, and Jewish businesses who prove they are not employing Arab workers shape identity? Identity development involves making sense of, and coming to terms with, the social world one inhabits, recognizing choices and making decisions within contexts, and finding a sense of unity within one's self while claiming a place in the world. Since there is no objective, ahistoric, universal trans-cultural identity, views of identity must be historically and culturally situated. This paper explores identity issues among members of the Palestinian Arab minority in Israel. While there is a body of literature exploring this subject, we will offer a different perspective by contextualizing the political and economic contexts that form an essential foundation for understanding identity formation among this minority group. We argue that, as a genre of settler colonialism, ‘pure settlement colonies’ involve the conquering not only of land, but of labor as well, excluding the natives from the economy. Such an exclusion from the economy is significant for its cultural, social, and ideological consequences, and therefore is especially significant in identity formation discussed in the paper. We briefly review existing approaches to the study of identity among Palestinian Arabs in Israel, and illustrate our theoretical contextual framework. Finally, we present and discuss findings from a new study of identity among Palestinian Arab college students in Israel through the lens of this framework.     

Bayesian analysis of human movement curves

Summary.  We consider the Bayesian analysis of human movement data, where the subjects perform various reaching tasks. A set of markers is placed on each subject and a system of cameras records the three-dimensional Cartesian co-ordinates of the markers during the reaching movement. It is of interest to describe the mean and variability of the curves that are traced by the markers during one reaching movement, and to identify any differences due to covariates. We propose a methodology based on a hierarchical Bayesian model for the curves. An important part of the method is to obtain identifiable features of the movement so that different curves can be compared after temporal warping. We consider four landmarks and a set of equally spaced pseudolandmarks are located in between. We demonstrate that the algorithm works well in locating the landmarks, and shape analysis techniques are used to describe the posterior distribution of the mean curve. A feature of this type of data is that some parts of the movement data may be missing—the Bayesian methodology is easily adapted to cope with this situation.     

A comparison between two simple measures of skewness

In 1995, Arnold and Groeneveld introduced the measure of skewness gammaM in terms of F(mode)-the cumulative probability of a random variable less than or equal to the mode of the distribution. They assumed that the mode of a distribution exists and is unique. Independently, in 1996, the present author arrived at the measure of skewness T, which is given in terms of F(mean). This measure possesses desirable properties and is equally simple. The measure gammaM satisfies - 1 gammaM 1 , with 1 (- 1) indicating extreme right (left) skewness. However, the measure T can take on any value on the real line; hence, an equivalent measure gammaT is considered and is compared with gammaM. We consider a variety of families of distributions and include in our study other measures of skewness of interest. Skewness values are easily obtained using MINITAB programs.     

A methodological strategy for a one-number census in the UK

As a result of lessons learnt from the 1991 census, a research programme was set up to seek improvements in census methodology. Underenumeration has been placed top of the agenda in this programme, and every effort is being made to achieve as high a coverage as possible in the 2001 census. In recognition, however, that 100% coverage will never be achieved, the one-number census (ONC) project was established to measure the degree of underenumeration in the 2001 census and, if possible, to adjust fully the outputs from the census for that undercount. A key component of this adjustment process is a census coverage survey (CCS). This paper presents an overview of the ONC project, focusing on the design and analysis methodology for the CCS. It also presents results that allow the reader to evaluate the robustness of this methodology.     

Understanding exponential smoothing via kernel regression

Exponential smoothing is the most common model-free means of forecasting a future realization of a time series. It requires the specification of a smoothing factor which is usually chosen from the data to minimize the average squared residual of previous one-step-ahead forecasts. In this paper we show that exponential smoothing can be put into a nonparametric regression framework and gain some interesting insights into its performance through this interpretation. We also use theoretical developments from the kernel regression field to derive, for the first time, asymptotic properties of exponential smoothing forecasters.     

住房抵押贷款对启动住房消费的作用

国际经验表明 ,当一国的人均 GDP达到 30 0 - 10 0 0美元时 ,正是启动住房市场的关键时期 ;而住房抵押贷款在扩大内需、实现住房有效需求的转化中起着重要的作用。本文通过分析当前住房抵押贷款业务中存在的主要问题 ,探究影响我国住房抵押贷款发挥作用的一些主要因素 ,并客观评价现阶段我国住房抵押贷款所能起的作用     

沙发检测装置应力及疲劳性能研究

为提高折叠沙发检测装置可靠性,满足技术机构开展检测工作的需求,提出采用有限元分析的方法,对装置的腿部、座部和背部受力单元进行应力和疲劳性能研究。根据应力云图优化装置结构,利用疲劳分析模块Fatigue Tool模拟装置耐久性能。模拟结果验证了装置耐久性设计的合理性。     

The life-course origins of mastery among older people

In this article, we aim to identify the sources of mastery--the understanding that individuals hold about their ability to control the circumstances of their lives. The sample for our inquiry was drawn from the Medicare beneficiary files of people 65 and older living in Washington, DC, and two adjoining Maryland counties. We find that past circumstances, particularly those reflecting status attainment and early exposure to intractable hardships, converge with stressors experienced in late life to influence elders' level of mastery. The impact of past conditions, however, does not necessarily directly affect the current mastery of older people. Instead, the effect of prior experiences on current mastery is mediated by what we refer to as life-course mastery: one's belief that one has directed and managed the trajectories that connect one's past to the present. Our analyses show that life-course mastery largely serves as the mediating channel through which individuals connect their past to their present.