Race and Reciprocity: Inter‐household Exchanges in a Multiracial Neighborhood

This study investigates the degree to which African‐American households are socially integrated into a multiracial, middle‐class suburban neighborhood near Dallas, Texas. Although U.S. neighborhoods are becoming increasingly heterogeneous in composition, little is known about black households' participation in social and informational networks within multiracial middle‐class neighborhoods. Drawing on theories of the gift and social capital, we view neighborhoods in terms of complex patterns of inter‐household exchanges of material and symbolic goods. We predict that black‐led households will exchange at a lower rate with their neighbors than will other households and test this prediction using survey data collected from 119 households and from follow‐up interviews with eight black heads of household. Our main finding from the survey is that black households exchanged at a significantly lower rate than did other households, ceteris paribus. The follow‐up interviews found little evidence of black racial homophily in neighboring or of racism within the neighborhood. However, the low rate of black inter‐household exchanges may be partly explained by black head of households' personal experiences of racism outside the neighborhood and by a racially constituted disposition against borrowing from neighbors. We discuss implications of our findings for research on racial integration and segregation.     

Forced Migration,Climate Change,Mitigation and Adaptive Policies in Mexico: Some Functional Relationships

Natural disasters related to hydro-meteorological events have increased during the last few decades, both in frequency and severity. Mexico is heavily exposed to climate change, but has also suffered in the past from climate variability ( Blümel, 2009 ). The new risks oblige the government to develop mitigation processes, while the affected people are implementing strategies of adaptation and resilience-building, mostly at the family and community level. This includes forced migration due to climate change into the slums of megacities or illegal immigration to the United States. The arid, semi-arid and subhumid condition of 49.2 per cent of the territory of Mexico is seriously affected by climate change. In addition, poverty and the lack of jobs have created complex livelihood situations, in which young people leave rural areas, partly due to socio-economic pull factors. In this paper, we address the functional relationships between climate patterns and migration processes in Mexico, highlighting the linkages between the origin of migrants, their economic activity and their vulnerability to extreme events and we discuss long-term climate patterns. Agriculture still uses 78 per cent of the available water in Mexico. In the drylands the competition for water use requires an integrated policy to deal with the new threats from climate change, including mitigation from the top down and adaptation processes from the bottom up to reduce the social vulnerability of the rural population in the highly affected drylands of the central and northern parts of Mexico. The new policy for administering water resources, which promotes the efficient use of an increasingly scarce and polluted resource, still suffers from a lack of participation by the affected rural population. In this paper, we propose an integrated management system from the watershed onwards, involving socio-economic, political, cultural and hydrological variables, to deal with the rising scarcity of water, and the uncertainty and complexity of climate change.     

PRODUCT MARKET REGULATION,FIRM SELECTION,AND UNEMPLOYMENT

This paper analyzes the effect of product market regulation (PMR) on unemployment in a search model with heterogeneous multiple‐worker firms. In our setup, PMR modifies the distribution of firm productivities, thereby affecting the equilibrium rate of unemployment. We distinguish between PMR related to entry costs and PMR that generates recurrent fixed costs. We find that: (i) higher entry costs raise the rate of unemployment mainly through our novel selection effect, (ii) higher fixed costs decrease unemployment through the selection effect and increase it through the competition effect analyzed in Blanchard and Giavazzi (2003, Quarterly Journal of Economics, 118, 879–907). Firm heterogeneity magnifies the impact of both types of regulatory costs. We propose econometric evidence consistent with the unemployment effects of sunk versus recurring costs.     

A Bayesian analysis of directional data using the projected normal distribution

This paper presents a Bayesian analysis of the projected normal distribution, which is a flexible and useful distribution for the analysis of directional data. We obtain samples from the posterior distribution using the Gibbs sampler after the introduction of suitably chosen latent variables. The procedure is illustrated using simulated data as well as a real data set previously analysed in the literature.     

Fast food and unnatural experiments: Another perspective on the New Jersey minimum wage

Conclusion  We have argued that the difference-in-differences method of examining the effects of the New Jersey minimum wage, especially when the differences in differences are measured shortly after the change, is questionable. That being the case, if we nonetheless take this method seriously, and if following Card and Krueger we look at the data shortly before and after the New Jersey minimum was imposed, then the only statistically significant evidence we can find supports the conclusion that the New Jersey minimum reduced employment of young workers.     

Linear statistical inference for global and local minimum variance portfolios

Traditional portfolio optimization has often been criticized for not taking estimation risk into account. Estimation risk is mainly driven by the parameter uncertainty regarding the expected asset returns rather than their variances and covariances. The global minimum variance portfolio has been advocated by many authors as an appropriate alternative to the tangential portfolio. This is because there are no expectations which have to be estimated and thus the impact of estimation errors can be substantially reduced. However, in many practical situations an investor is not willing to choose the global minimum variance portfolio but he wants to minimize the variance of the portfolio return under specific constraints for the portfolio weights. Such a portfolio is called local minimum variance portfolio. Small-sample hypothesis tests for global and local minimum variance portfolios are derived and the exact distributions of the estimated portfolio weights are calculated in the present work. The first two moments of the estimator for the expected portfolio returns are also provided and the presented instruments are illustrated by an empirical study.     

Developing green innovation performance by fostering of organizational knowledge and coopetitive relations

This study explores the links between knowledge base, relationship learning, and green innovation performance within a coopetitive framework. We posit that green innovation is directly influenced by a broad and deep knowledge base. We also hypothesize that the knowledge base–green innovation performance link is positively mediated by relationship learning (indirect effect). These hypotheses were empirically tested using consistent partial least squares path modeling. A sample of 112 firms from the Spanish automotive components manufacturing sector was used. The mediating effect of relationship learning on the knowledge base–green innovation performance link was observed to be positive and significant. Therefore, managers should build strong relations with stakeholders to assimilate, transfer, and adapt new knowledge and thus enhance green innovation performance.     

AN OVERVIEW OF TRADEOFF CURVES IN MANUFACTURING SYSTEMS DESIGN

In this paper we review the use of tradeoff curves in the design of manufacturing systems that can be modeled as open queueing networks. We focus particularly on the tradeoff between expected work-in-process (or product leadtime) and capacity investment in job shops. We review the algorithms in the literature to derive tradeoff curves and illustrate their application in evaluating the efficiency of the system, in deciding how much capacity to have, how to allocate resources between the reduction of uncertainty and the introduction of new technologies, and how to assess the impact of changes in products throughput and product mix. The methodology is illustrated with an example derived from an actual application in the semiconductor industry.     

A mixed-method exploration of functioning in Safe Schools/Healthy Students partnerships

This paper presents a mixed-method approach to measuring the functioning of Safe Schools/Healthy Students (SS/HS) Initiative partnerships. The SS/HS national evaluation team developed a survey to collect partners’ perceptions of functioning within SS/HS partnerships. Average partnership functioning scores were used to rank each site from lowest to highest. Sites with the most favorable perceptions of partnership functioning were defined as having average scores in the top 10% (n = 10) and sites with the least favorable perceptions of partnership functioning were defined as having average scores in the bottom 10% (n = 10). Qualitative data for these 20 sites were inductively open coded for emergent themes and analyzed for patterns using grounded theory approach. Six themes emerged that distinguished sites reporting the most favorable and least favorable perceptions of partnership functioning: partner engagement, facilitators, barriers, shared decision making, partnership structure, and sustainability. Sites reporting the most favorable perceptions of partnership functioning effectively utilized collaboration processes that facilitate coalition building, such as shared decision making, effective communication, and developing a clearly defined structure. Qualitative themes from this analysis provide evidence of validity for the partnership functioning scale used and illustrate distinguishing features between sites with the most favorable and least favorable perceptions of partnership functioning.     

From 'human being' to 'social subject': "unfreezing" ergonomics and the implications for understanding and intervening health-disease process

Ergonomics has been successful in increasing productivity and comfort in the work arena. It has also contributed to reducing occupational accidents. Despite this, ergonomics is frequently limited to understanding the health-disease process related to human-technology interactions, as this process is more complex than what can be understood from an ergonomic evaluation. Recognising this limit, this work ontologically and epistemologically contrasts the notions of 'human being' and 'social subject', and concludes that the study object of ergonomics, or human-technology interaction, greatly depends on social aspects that nowadays are not tackled explicitly: route (history), project, structure, agency, motivations and power. It also analyses how participatory ergonomics tacitly includes many of these aspects, including some implications that the change of notion, from 'human being' to 'social subject', brings to the understanding of the health-disease process and the reduction of associated risks during human activities.