Une condition d’invariance du modèle de régression à coefficients aléatoires

Cet article développe une condition d’invariance du modèle de régression à coefficients aléatoires (RCA) et de cette façon permet : (i) d’étendre les résultats de Rao (1963, 1967)”; (ii) de fournir une nouvelle démonstration de l’égalité des estimateurs des moindres carrés généralisés directs et ceux en deux étapes du modèle RCA”; et (iii) de rectifier une proposition de McAleer (1992) pour les modèles mixtes.This paper develops an invariance condition for the random coefficients regression (RCR) model and thereby: (i) exends the results originally proposed by Rao (1965, 1967); (ii) provides a new proof of the equality of the direct and two-step estimators of the RCR model; and (iii) corrects a result claimed in McAleer (1992) for mixed models

Introduction to The Chinese and the Iron Road

Excerpt from The Chinese and the Iron Road: Building the Transcontinental Railroad, edited by Gordon H. Chang and Shelley Fisher Fishkin, with Hilton Obenzinger and Roland Hs

The ghost of the ‘Y’ : paternal DNA, haunting and genealogy

Based on a personal family history experience, in this paper, I consider the way in which genealogical DNA testing is revealing family secrets, in particular paternity secrets, which would previously have remained unknown via ‘traditional’ methods of genealogical research. Reasons for the displacement of these invisible fathers from the records are discussed, and the power of genealogical DNA testing to bring them into focus is examined. Such discoveries may disrupt and unsettle, causing people to think differently about the fathers and grandfathers with whom they have grown up or have believed to be part of their personal histories and, for some people, may challenge their sense of identity. Beyond personal identity issues, in this paper, I draw upon ideas about ‘ghost-work’ to suggest that these experiences have some of the features of hauntings and that the ghostly fathers who break through may speak to us about social realities and structures, beyond the confines of linear tim

Disseminating the Administrative Version and Explaining the Administrative and Statistical Versions of the Federal Poverty Measure

This article describes how the author, a federal employee, disseminates and explains the poverty guidelines (the administrative version of the federal poverty measure, used in determining eligibility for certain programs) and other povertyrelated information, responding to 1312 public inquiries in 1996. The article reviews federal programs and some non-federal activities using the poverty guidelines; the principal categories of people who make poverty inquiries; and some of the questions most commonly asked. One common question is How was the poverty line developed? The author has prepared a detailed account of the development and history of the poverty thresholds (the original version of the poverty measure), as well as a history of unofficial poverty lines in the U.S. between 1904 and 1965; these papers are disseminated in response to public inquiries on those subjects. The article discusses several findings about the development of poverty lines in the U.S. as a social process

Une condition d’invariance du modèle de régression à coefficients aléatoires*

This paper develops an invariance condition for the random coefficients regression (RCR) model and thereby: (i) exends the results originally proposed by Rao (1965, 1967); (ii) provides a new proof of the equality of the direct and two-step estimators of the RCR model; and (iii) corrects a result claimed in McAleer (1992) for mixed models. Cet article développe une condition d’invariance du modèle de régression à coefficients aléatoires (RCA) et de cette façon permet : (i) d’étendre les résultats de Rao (1963, 1967)”; (ii) de fournir une nouvelle démonstration de l’égalité des estimateurs des moindres carrés généralisés directs et ceux en deux étapes du modèle RCA”; et (iii) de rectifier une proposition de McAleer (1992) pour les modèles mixtes.

Party membership and campaign activity in Britain: The impact of electoral performance

The article examines the impact of electoral results on party membership and activity. Previous studies have focused on the long-term effects of electoral success or failure, suggesting that they may produce a spiral of demobilization or mobilization. The article shows that the dramatic change of electoral fortunes experienced by British parties at the 1997 general election broke this spiral, with the outcome leading to significant changes in the health and activity of local parties. It is concluded that dramatic election results can have significant implications for party organization

The relative electoral impact of central party co-ordination and size of party membership at constituency level

Over the past decade, clear evidence has been produced showing that effective constituency campaigning in British general elections can lead to better electoral performance. This evidence has challenged the received wisdom that only national campaigning is significant and that efforts at local level are meaningless rituals. Denver et al. have focused on the role of the national parties in strengthening local campaigns in target seats; Seyd and Whiteley, by contrast, have stressed the importance of local party membership. This article attempts to assess the relative electoral impact of national party co-ordination and constituency party membership and suggests that the impact of these two factors varies by party

The performance of beams and columns continuously braced with diaphragms

INTRODUCTION In Progress Report No.1, it was reported that the initial conception of the problem was that diaphragms act almost exclusively in shear when called upon to brace compression members, and that it had been decided to test single columns with finite widths of diaphragm attached, with width of the sheet being varied to provide a range of lateral support up to that which permitted full column strength, based on strong axis to be developed. However, the first test of this kind, Test CB-l, clearly indicated that the diaphragm acted essentially in flexure only and thus had the same effect as if it were regarded as a weak cover plate. It was already quite clear at the time of the First Progress Report that the shear contribution of the diaphragm was practically nil, based on observation of combined beam-sheet tests (refer to figure 1, First Progress Report). It was thought at that time that prevention of rotation of the ends of the diaphragm would produce shear-predominant action. While the sheet, thus restrained, provided far more support to the beam than in the previous tests and could be exactly calculated, the behavior was essentially flexural and not in shear. A series of tests were proposed in Progress Report No. 1 to confirm the initial conclusion that supporting diaphragms act in flexure and function essentially as corrugated cover plates. As mentioned, this was exactly confirmed by the first test, making further tests of this character pointless. It was recognized furthermore, that any purely flexural contribution of the sheet was so small that nothing was to be gained in design, in terms of increased column strength, by counting on it. On the other hand, by experience and intuition, it seemed that the supporting ability of the sheet should be far greater than observed. In rethinking the problem, it was concluded that the sheet could act in pure shear and provide the anticipated support only if all crosssections were prevented from roaating. The simplest situation producing this condition is that of a diaphragm attached to two identical, (in all respects, including loading), columns or beams, as in figure 27. In fact, this is a rather realistic situation in that corrugated building siding is or could be attached continuously across two or more columns that are more or less identical. Accordingly, it was decided that tests should be performed on pairs of columns, each loaded and supported separately and identically, but connected by a diaphragm, as in figure 14. To the inrestigators\u27 knowledge, tests of this kind had never been performed, and were regarded as exceedingly difficult because of the necessity of centering with absolute certainty two interconnected and interacting columns. As a simpler and less tedious way of checking the notion that the diaphragm would act primarily in shear, beam sheet tests as in figure 4 were devised. These tests, performed with a variety of diaphragms, gave substantial assurance that the idea was correct and permitted the experimental determination of the effective shear rigidities. With the information thus obtained, several double column tests were performed