Optimal scaling of Metropolis algorithms: Heading toward general target distributions

The authors provide an overview of optimal scaling results for the Metropolis algorithm with Gaussian proposal distribution. They address in more depth the case of high‐dimensional target distributions formed of independent, but not identically distributed components. They attempt to give an intuitive explanation as to why the well‐known optimal acceptance rate of 0.234 is not always suitable. They show how to find the asymptotically optimal acceptance rate when needed, and they explain why it is sometimes necessary to turn to inhomogeneous proposal distributions. Their results are illustrated with a simple example.     

Construction and selection of quick switching double-sampling system: sample size tightening

A new sampling inspection system involving normal and tightened plans is presented. Performance measures are developed. The average sample number of the newly developed system is compared with those of existing plans. Procedures are indicated an tables are constructed for designing the system indexed by various combinations of parameters.     

Race and gender as bases of class fractions and their effects on earnings

Maints auteurs ont affirmé que la race et le sexe repreésentent des bases de fractions de classe en ce sens que leur construction sociale permet à des segments d'une classe de se constituer à partir de caractéristiques liées à la race et au sexe. Cependant, les études ernpiriques antérieures tendent à considérer seulernent la race et le sexe comme des facteurs de fractionnernent au sein de la classe ouvrière seulement. À l'aide des données du recensement de 1986, cette communication analyse lea effets interactifs de la race et du sexe sur le revenu considéré comme facteur de fractionnement des classes. Les recherches de l'auteur indiquent que les effets produits par le groupement par race et par sexe sont inégaux en ce qui trait au revenu, les hommes gagnant davantage que les femmes tout en étant davantage ‘fractionnés’ par le revenu que les femmes. Lorsqu'on fait abstraction des différences de revenu entre classes, la race et le sexe demeurent des facteurs explicatifs importants du niveau de revenu, bien que leurs effets soient plus marqués chez les cadres, les professionnels et les ouvriers. L'écart entre les sexes est plus prononcé, mais la race demeure importante comme facteur de fractionnement au niveau des revenus des homrnes, měme après correction pour tenir cornpte d'autres variables. L'auteur affirme que l'assimilation des relations de sexe et de race aux relations entre classes est insatisfaisante et qu'il existe de sérieuses considérations théoriques pour considérer que les causes des inégalités entre les sexes et les races se trouvent non seulement à l'intérieur du domaine de la production, mais également à l'extérieur de celui-ci. The literature has argued that race and gender are bases of class fractions in that their social construction enables segments of a class to be constituted on racialized and gender-linked characteristics. However, previous empirical works tend to consider race or gender as fractionalizing the working class only. Using the 1986 Census data, this paper analyses the interactive effects of race and gender on earnings as grounds of fractionalizing classes. The findings indicate that race and gender groupings produce unequal effects on earnings: males have an income advantage over females, but race fractionalizes the earnings of men to a greater extent than for women. When inter-class differences in earnings are removed, race and gender remain important in explaining earnings, although their effects are stronger among the managerial, the professsional, and the working class. The gender gap is more pronounced, but race remains important in fractionalizing the earnings of men even after controlling for other variables. The paper argues that it is insufficient to subsume gender and race relations under class relations, and that there are compelling theoretical grounds to consider gender and race inequality as having roots both within and outside the sphere of production.     

Forced to work and liberated from work

The work-welfare nexus is essential in all social policy regimes. The question is in what situations individuals should be entitled to social welfare benefits and in which situations they should be obliged to work. Social welfare law and administrative practices define mechanisms that separate the deserving poor from people able to work. This article analyses the functions and character of these "separation mechanisms" in Sweden during three periods in history: a) in rural society in the late 19th century; b) in industrial society during the successful years of the Swedish model from World War II until the late 1970s; and c) the present, including the period of welfare retrenchment and reconsideration since the early 1980s. The conclusion is that Swedish social policy has always been strongly work-oriented, but the specific form and content of the work ethic has varied under the influence of different ideologies and handled in different social policy institutions. Under specific conditions the work line has been either generous or restrictive and it has been based on structural attempts to improve the opportunities to work as well as on attempts to strongly pressure the individual to work. The work line of today is seen as an interesting attempt to combine an effort to create good work through improved work conditions and an effort to reinforce elements of work enforcement in the social insurance system.     

A Tabu Search Heuristic for the Location of Multi-Type Protection Devices on Electrical Supply Tree Networks

The problem of determining the number of multi-type protection devices and their locations on electrical supply tree networks with subtree dependency is investigated. The aim is to reduce the amount of inconvenience caused to customers that are affected by any given fault on the networks. An appropriate implementation of tabu search is proposed. We exploit a variable neighborhood and a soft aspiration level, and we embed a data structure and reduction tests into the search to speed up the process. Computational tests are performed on randomly generated electrical tree networks varying in size and branch complexity with encouraging results.     

La médiane simpliciale d'Oja: Existence,unicité et stabilité

Oja (1983) examined various ways of measuring location, scatter, skewness, and kurtosis for multivariate distributions. Among other measures of location, he introduced a generalised median known in this paper under the name of the Oja median. In our study of the existence of that median, we show that Oja's definition can only be applied to distributions having a mean. In dimension d θ 2, we establish that the usual method of extension breaks down, which raises the question of the validity of the concept as a notion of median. Two fundamental theoretical properties of that median are also considered: uniqueness and consistency.     

Why Did House Members Vote for H.R. 4437?1

This article examines why members of the U.S. House of Representatives voted for H.R. 4437, the controversial 2005 bill to construct a 700‐mile immigration barrier along the U.S.‐Mexican border and to criminalize illegal presence and aid to undocumented immigrants. Logit analysis suggests that being a first‐term House member or a Republican and representing a district that was in the South or the West or heavily blue‐collar substantially boosted the odds of supporting H.R. 4437. If a member's district was disproportionately Asian, Latino, or, especially, African American, he or she was instead more likely to oppose the measure.     

Empowering part-time nurses in the treatment of depressed inpatients.

1. With the consistent number of part-time nurses in the workforce, hospitals would benefit by more actively integrating them into professional nursing practice. 2. Empowering part-time nurses by affording them the opportunity to provide primary care has the potential to effectively use part-time personnel, decrease the workload for full-time staff, offer more flexibility in scheduling, and result in savings for hospitals in terms of nursing recruitment and retention. 3. This program has successfully developed and implemented a model of primary nursing that places three part-time nurses on a team capable of handling two to three primary patients. The success of this model has been attributed to excellent communication, trust in one another's professional skills, and nursing expertise.