Comparing relative importance of the same component in a series system in two environments

The relative performance of a component of a series system in two different environments is considered. The conditional probability of the failure of the system due to the failure of the specified component given that the system failed before time t is regarded as a measure of relative importance of the component to the system. A U-statistic test for checking the equality of the relative importance of the component to the system in two different environments against the alternative that the relative importance is smaller in one of the environments, is proposed. Some simulation results for estimating the power of the test are reported. The proposed test is applied to one real data set and it is seen that a different aspect of the data is brought out by this comparison than that by the comparisons of the absolute importance functions such as the subsurvival functions, considered in earlier studies.     

Culture and Co‐residence: An Exploration of Variation in Home‐Returning among Canadian Young Adults*

Cet article s'inscrit dans la lignée des études sur les dimensions culturelles de la cohabitation entre générations en examinant de près le comportement des jeunes adultes canadiens qui retournent vivre chez leurs parents. Nous explorons les rapports mutuels entre la famille et la diversité culturelle, entre le capital financier et le capital social, et entre le rythme et les mécanismes de transitions précoces qui se manifestent au cours d'une vie. Les modéles de hasards proportionnels sont appliqués à un sous‐échantillon de 2 549 jeunes adultes, àgés de 19 á 34 ans, en tenant compte des données de l'Enquete sociale générale, cycle 10, de 1995. L'une des principales conclusions tirées ici indique que les jeunes qui sont de langue maternelle anglaise sont beaucoup plus susceptibles de retourner chez leurs parents après un premier départ que ceux dont la langue maternelle est le français ou une autre langue. Les autres variables qui entrent en jeu sont le niveau d'education du père, le nombre de frères et de soeurs, le sexe, l'âge au moment du depart de la maison et la raison de ce départ. L'article aborde aussi les questions des responsabilités et des rôles des parents autour de la cinquantaine, et de la socialisation au sein de la famille au cours de la vie. This article offers a focussed examination of variation in home‐returning behaviour among Canadian young adults. Framed within the life course perspective, we explore the interrelationships among family and cultural diversity, financial and social capital, and the timing and pathways of early transitions. Proportional hazards analyses are performed on a subsample of 2,549 young adults aged 19–34, using data from the 1995 General Social Survey, Cycle 10. A major finding is that those whose mother tongue is English are significantly more likely to return to the parental home than those with French or “other” mother tongues. Other variables include: father's education, number of siblings, gender, age at home‐leaving, and initial reason for home‐leaving. Implications for midlife parental roles and responsibilities, and for family socialization are discussed.     

The incorporation of gender scholarship into sociology

The prospects of an intellectual revolution in sociology informed in part by a feminist perspective loomed large in the early 1970s. Following Ward and Grant's (1985) empirical examination of gender and feminist scholarship in sociology journals between 1974 and 1983, our research provides an empirical assessment of the “second ten years” after the feminist critique of the discipline, 1984–1993. Specifically, we examine the incorporation of gender-content scholarship into mainstream sociology journals. Our research also assesses the extent to which gender-content scholarship published in these journals is feminist-oriented or not and the extent to which this is influenced by the sex of authors, the type of journal, and the sex composition of editorships and editorial boards. Our findings indicate that although there were more gender- and feminist-oriented articles published in the recent ten-year period, proportionally there were fewer feminist-oriented articles than in the previous ten-year period. Our findings suggest that a feminist revolution in sociology is not likely to occur anytime soon, although the assimilation of feminist scholarship into sociology is occurring along the lines of other critical intellectual movements in recent decades. David V. Waller current research focuses on intellectual and social changes in the social sciences including the impact of electronic journals on communication among scientists, and on the geopolitical and economic determinants of change in the contemporary world system. Dana Dunn has authored articles on gender stratification, sex-based earnings inequality, and women in political office, and is editor of Workplace/Women's Place, a textbook addressing women's experiences in the workplace. Please direct all correspondence to David V. Waller, Assistant Professor of Sociology, Department of Sociology and Anthropology, Box 19599, University of Texas, Arlington, TX 76019 or to Waller@uta.edu.     

Design and evaluation of skip-lot sampling inspection plans with double-sampling plan as the reference plan

This paper presents a design for skip-lot sampling inspection plans with the double-sampling plan as the reference plan, so as to reduce the sample size and produce more efficient plans in return for the same sampling effort. The efficiency of the proposed plan compared with that of the conventional double-sampling plan is also discussed. The need for smaller acceptance numbers under the plan is highlighted. Methods of selecting the plan indexed by the acceptable quality level and limiting quality level, and by the acceptable quality level and average outgoing quality level are also presented.     

The foundations of econometrics-are there any

The conclusions of alogically consistent economic theory which strictly adheres to Aristotle's axioms of logic are factually true if its sufficient conditions are all factually true. Alternatively, if a conclusion of such a theory is false, then at- least one of its assumptions is false. Unfortunately, the factual truth of sufficient conditions cannot be established because the problem of induction i s impossible t o solve. It is algo true that the falsity of a conclusion cannot be established in the presence of uncertainty. While the philosophy of instrumentalism applied to sufficient and logically consistent explanations may provide useful solutions to immediate practical problems, the principles of simplicity, parsimony and profligacy--all of them requiring conditional deductive arguments--are useless as criteria for model choice.     

Urban tree cover: an ecological perspective

Analysis of urban tree cover is generally limited to inventories of tree structure and composition on public lands. This approach provided valuable information for resource management. However, it does not account for all tree cover within an urban landscape, thus providing insufficient information on ecological patterns and processes. We propose evaluating tree cover for an entire urban area that is based on patch dynamics. Treed patches are classified by their origin, structure, and management intensity. A patch approach enables ecologists to evaluate ecological patterns and processes for the entire urban landscape and to examine how social patterns influence these ecological patterns and processes.