A semi-parametric approach to robust parameter design

Parameter design or robust parameter design (RPD) is an engineering methodology intended as a cost-effective approach for improving the quality of products and processes. The goal of parameter design is to choose the levels of the control variables that optimize a defined quality characteristic. An essential component of RPD involves the assumption of well estimated models for the process mean and variance. Traditionally, the modeling of the mean and variance has been done parametrically. It is often the case, particularly when modeling the variance, that nonparametric techniques are more appropriate due to the nature of the curvature in the underlying function. Most response surface experiments involve sparse data. In sparse data situations with unusual curvature in the underlying function, nonparametric techniques often result in estimates with problematic variation whereas their parametric counterparts may result in estimates with problematic bias. We propose the use of semi-parametric modeling within the robust design setting, combining parametric and nonparametric functions to improve the quality of both mean and variance model estimation. The proposed method will be illustrated with an example and simulations.     

Telecommuting: The future of work, corporate culture, and American society

Conclusion Throughout American history, first on the family farm and now in modern day business institutions, the workplace has been a stabilizing institution in American society that has anchored the ongoing, informal interactions occurring outside the workplace. In 1900, few Americans had a private mode of transportation. Barely 4,000 passenger automobiles were sold in 1900, and while horses were common, they were used primarily for farming, public transportation, and commercial activity in cities. By 1930, nearly 40 million cars had been added to America’s streets. The automobile recast life and work in central cities and eventually the suburbs.     

Do Lets Work?

This study aims to uncover some of the reasons for differences in attitudes towards family‐friendly and equal opportunities (EO) policies for women between senior and junior staff and between male and female staff. This in‐depth case study of a multi‐national corporation in Hong Kong that included a survey questionnaire, interviews and participant observation suggests four categories of female employees according to their approach to EO: advocators, supporters, outsiders and rejecters. The approach adopted was dependent on the woman's level of empathy towards the situation of working women and the extent of her career ambition. Four categories of male employees can also be classified depending on their level of empathy towards women's situation (similar to women's case) and their extent of career satisfaction (in contrast to women's career ambition), namely, antagonists, outsiders, fence‐sitters and sympathizers. Women at higher levels were less supportive of EO than women at lower levels. No such clear relationship between organizational level and attitudes towards EO was observed among men. In Hong Kong, female managers had little expectation that their organization would be family‐friendly and women workers who consciously chose to balance work and family accepted that it meant fewer promotional chances. No such self‐adjusted depressed ambition was observed among men.     

Efe fathers: one among many? A comparison of forager children's involvement with fathers and other males

The study reported describes Efe (pygmy) forager one-, two-, and three-year-olds' involvement with males. The Efe of northeastern Zaïre were chosen because their social organization allows us to examine hypotheses based on studies in Western, technologically complex societies about the distinctive role fathers play in the lives of their young children. Behavioral observations of Efe children's day-to-day activities with fathers, men and boys were recorded using a focal subject sampling technique (Altmann, 1974). Two behavioral measures were created to capture the extent to which males were involved with children: Social engagement describes males' involvement with children and social attention describes eavesdropping by children on males' everyday activities. Eight one-year-olds, 7 two-year-olds and 8 three-year-olds were each observed for six, one-hour observation sessions that were distributed evenly over the daylight hours. Data were analyzed using the traditional measure of involvement (e.g., adult males) and using a newly developed measure of the involvement of the average individual (e.g., average adult mate). Comparisons at each of the ages showed that fathers were consistently like other men in the extent to which children participated in social activities with them and watched their activities. Only fathers' level of social engagement declined significantly as children grew older. Boys' role relative to other males became increasingly distinctive as children aged. The findings suggest that Efe fathers may not be unique in the same sense assumed by Western study ideals, and raise questions about the special status given to fathers in Western theory and data. The patterning of mate involvement with children is discussed in terms of Efe community life, and in terms of Efe children's developing understanding of their relationship with fathers and other males.     

BAYESIAN SUBSET SELECTION AND MODEL AVERAGING USING A CENTRED AND DISPERSED PRIOR FOR THE ERROR VARIANCE

This article proposes a new data‐based prior distribution for the error variance in a Gaussian linear regression model, when the model is used for Bayesian variable selection and model averaging. For a given subset of variables in the model, this prior has a mode that is an unbiased estimator of the error variance but is suitably dispersed to make it uninformative relative to the marginal likelihood. The advantage of this empirical Bayes prior for the error variance is that it is centred and dispersed sensibly and avoids the arbitrary specification of hyperparameters. The performance of the new prior is compared to that of a prior proposed previously in the literature using several simulated examples and two loss functions. For each example our paper also reports results for the model that orthogonalizes the predictor variables before performing subset selection. A real example is also investigated. The empirical results suggest that for both the simulated and real data, the performance of the estimators based on the prior proposed in our article compares favourably with that of a prior used previously in the literature.     

Sociological computing: An opportunity missed?

Rapid advances in sociological computing are changing virtually every aspect of scholarly sociological work. These changes offer an opportunity for sociologists to improve the quality of their work and bring new insights and approaches to bear on important sociological problems. Nevertheless, sociologists display a profound ambivalence toward computer work by other sociologists. Left unchecked, this ambivalence threatens to turn sociological computing into an opportunity missed. Inadequate rewards, lack of training, and a general failure to understand the importance of computing in sociology threaten to stifle the development of quality soft-ware, push sociologists competent in computing into other fields, and jeopardize the quality of sociological scholarship. This article documents these ambivalent tendencies and proposes reasonable steps the discipline should take to assure that sociological computing does not become an opportunity missed.     

Population Policy in Early Victorian England

This paper argues that the generally-held belief that there was no population policy in Great Britain during its fertility transition is incorrect. There were, in fact, clear and implicit and explicit policies in place by the early 19th Century which aimed at reducing population growth. These were negative, involving elimination of family allowances (the famous Poor Laws), and also positive, through subsidised emigration and ``transportation' of felons to the colonies. Moreover, a changed ``ideation' on the part of the nation's political, intellectual and spiritual leaders, changed norms about marriage and child-bearing, raising sharply the perceived economic and psychic cost of children. Lacking acceptable means to control pregnancies, many working class women resorted to abortion, infanticide and child abandonment to reduce their family size. The policy's actual impact on overall fertility is uncertain but it did constitute a deliberate attempt by society to affect demographic behaviour and outcomes.     

The Migration–Development Nexus: Evidence and Policy Options

Migration and development are linked in many ways – through the livelihood and survival strategies of individuals, households, and communities; through large and often well–targeted remittances; through investments and advocacy by migrants, refugees, diasporas and their transnational communities; and through international mobility associated with global integration, inequality, and insecurity. Until now, migration and development have constituted separate policy fields. Differing policy approaches that hinder national coordination and international cooperation mark these fields. For migration authorities, the control of migration flows to the European Union and other OECD countries are a high priority issue, as is the integration of migrants into the labour market and wider society. On the other hand, development agencies may fear that the development policy objectives are jeopardized if migration is taken into consideration. Can long–term goals of global poverty reduction be achieved if short–term migration policy interests are to be met? Can partnership with developing countries be real if preventing further migration is the principal European migration policy goal? While there may be good reasons to keep some policies separate, conflicting policies are costly and counter–productive. More importantly, there is unused potential in mutually supportive policies, that is, the constructive use of activities and interventions that are common to both fields and which may have positive effects on poverty reduction, development, prevention of violent conflicts, and international mobility. This paper focuses on positive dimensions and possibilities in the migration–development nexus. It highlights the links between migration, development, and conflict from the premise that to align policies on migration and development, migrant and refugee diasporas must be acknowledged as a development resource.     

Children's involvement in their parents' divorce: implications for practice

The paper reports findings from a research study that explored children's experience of divorce. It shows that children experience parental divorce as a crisis in their lives but that they are able to mobilise internal and external resources to regain a new point of balance. In doing so, children demonstrate the degree to which they are active and competent participants in the process of family dissolution. The implications of the data are then considered in relation to engaging with children involved in divorce and in relation to some of the cultural presumptions that might militate against hearing what they have to say about their experiences. Copyright © 2002 John Wiley & Sons, Ltd.