An international trade model to capture linkages among supply-constrained economies

The development of a country's domestic and international markets depends on its own actions as much as on those of its trading partners. The study of market linkages is thus vital for policy making. Borrowing from the conceptual framework of Leontief's input-output analysis and from the national accounts equation, this paper presents a new model to calculate multilateral trade multipliers while minimizing data requirements. The novelty of the approach consists in the column-wise (supply-oriented) normalization of trade as opposed to the row-wise (demand-oriented) normalization that prevails in the literature. The explanatory power of the model has been successfully tested on data that refer to 1973–1974. Divergence from reality inevitably reflects the great fluidity that characterized trade during that period. Although most successful when applied to trade among supply-oriented economies (such as those of socialist or developing countries), at present empirical tests have been run only for a handful of OECD and OPEC countries.     

Measurement of the subjective work environment

This paper considers the various issues that frame the development and use of measures of the subjective work environment. It begins by questioning the role of the work environment in determining occupational health, and explores the possible mechanisms by which that environment might exert its influence. It concludes that one of the important final common pathways is psycho-physiological in nature, and is rooted in individual perception and cognition and the experience of stress. Important for this model are the concepts of mediation and moderation. The measurement of the subjective work environment has often been idiosyncratic to the study in hand, and there are few well-established measures in common use. It is argued that researchers should be careful when deciding not to use established measures and effectively 'invent' their own. In developing new measures, decisions have to be made concerning the nature of the measure along with its 'granularity' and complexity. It is also argued that it is important that researchers should follow good psychometric practice in the development of those measures. Suggestions for 'good practice' are discussed. Attention is drawn to the issues of reliability and validity, and this paper discusses the role of triangulation in the planning and execution of data collection and analysis. The paper ends by reviewing the recommendations made towards the development and use of measures of the subjective work environment.     

Only one pair of hands: Ways that single mothers stretch work and family resources

Based on in-depth interviews with 50 women in the eastern part of Massachusetts in the United States between the ages of 22 and 50 who have chosen to be single mothers, this article presents a typology demonstrating the factors leading to, and consequences of, differing combinations of economic and social support for childrearing marshaled by the mothers. Ensuring middle class lives for their children is a central goal for the mothers. This goal determines how and why the mothers construct specific strategies to complement their ‘one pair of hands’ based on resources they develop: some have both financial resources and a deep network of support (‘good jobs/good friends’), others have either one or the other (‘tapping the networks’ and ‘looking to the market’), and a fourth group have neither (‘going it alone’). Despite variation in resources all the women seek ways to tip the balance of work and family in favor of mother-time, and in the process of developing individual solutions activate broad kin and community networks.     

Optimal population control with uncertain output

"This note has shown how the techniques of stochastic control theory can be used to analyze the impact of uncertainty about non-labour inputs on optimal population control expenditure. While we have chosen very simple structure, it has allowed us to isolate the channels through which uncertainty affects the optimal plan, in this case causing expected expenditure on control to rise more slowly or fall more rapidly than its deterministic counterpart. Given the long-term implications of changes in population growth at any instant, and the stochastic nature of the environment in which control decisions are made, it is likely that useful insights could be obtained by extending the stochastic control approach to more complicated population control structures."     

Individual strategies for coping with stress at work: A review

This paper discusses some of the conceptual and methodological issues involved in the study of coping. It focuses on individual coping with work and work-related problems, and adopts a transactional framework for the definition of the key concepts of stress, appraisal and coping. It identifies and reviews 17 recent papers which are representative of the coping literature, as defined by the scope of the paper. What it draws out of this review largely concerns issues of measurement, and four particular issues are flagged as important for future research. It concludes that there is a need for more and more adequate studies, particularly in relation to the classification and modelling of coping, and that the adequacy of those future studies should be partly judged in terms of how well they deal with the issues raised here.     

Past,present and future: how the Lithuanian Diaspora in the Netherlands accumulates human capital from social capital

This paper explains how social capital activates the accumulation of human capital within a Diaspora context. Our study focused on migrants in the Lithuanian Diaspora and revealed unexpected differences in the way low- and high-skilled migrants developed and applied social capital in order to accumulate human capital. Namely, despite a less privileged point of departure, low-skilled Lithuanians appeared stronger in developing new social networks, and were more driven to strengthen their human capital than high-skilled migrants. The study provides novel empirical and theoretical insights by explaining the significance of social capital in the accumulation of human capital among Diaspora communities. In so doing, the study provides important insights for integration policy development for immigrant-receiving countries, offering a different perspective on high- and low-skilled migrant mobility and integration intentions.     

Model comparison for a complex ecological system

Summary.  The ecological consequences of climate change and its interaction with other environmental pressures, such as nutrient pollution, are little understood. For freshwater ecosystems, knowledge of these combined effects is required for water resource management and in particular for successful implementation of the European Community Water Framework Directive 2000, which requires that all surface-waters should be at, or above, 'good status' by 2016. Statistical analysis of detailed long-term environmental data sets can be used to explore these combined effects. Loch Leven (Scotland) has been routinely monitored since 1967, providing one of the largest and most extensive of such data sets. Over this period there has been evidence of climate change and a period of eutrophication and recovery at the loch. Transfer functions, additive models and varying-coefficient models are used to explore the complex ecological system at Loch Leven with the aim of obtaining insight into the combined effects of climate change and eutrophication on water quality.     

The Value of Quality Grading in Remanufacturing

In this paper we consider a tactical production‐planning problem for remanufacturing when returns have different quality levels. Remanufacturing cost increases as the quality level decreases, and any unused returns may be salvaged at a value that increases with their quality level. Decision variables include the amount to remanufacture each period for each return quality level and the amount of inventory to carry over for future periods for both returns (unremanufactured), and finished remanufactured products. Our model is grounded with data collected at Pitney‐Bowes from their mailing systems remanufacturing operations. We derive some analytic properties for the optimal solution in the general case, and provide a simple greedy heuristic to computing the optimal solution in the case of deterministic returns and demand. Under mild assumptions, we find that the firm always remanufactures the exact demand in each period. We also study the value of a nominal quality‐grading system in planning production. Based on common industry parameters, we analyze, via a numerical study, the increase in profits observed by the firm if it maintains separate inventories for each quality grade. The results show that a grading system increases profit by an average of 4% over a wide range of parameter values commonly found in the remanufacturing industry; this number increases as the returns volume increases. We also numerically explore the case where there are capacity constraints and find the average improvement of a grading system remains around 4%.