1,168 research outputs found
Ethnic Segregation and Educational Outcomes in Swedish Comprehensive Schools
We ask whether ethnic density in Swedish comprehensive schools affect teacher-assigned school grades in ninth grade (age 16). The data, based on two entire cohorts who graduated in 1998 and 1999 (188,000 pupils and 1,043 schools), link school information with Census data on social origin, and enable us to distinguish first- from second generation immigrants. Using multilevel analysis we find the proportion of first, but not the second, generation immigrant pupils in a school to depress grades in general, but particularly for (first generation) immigrant pupils. Passing a threshold of more than 40 percent immigrants reduces grades with around a fifth of a standard deviation, affecting fourteen percent of immigrant children. Our main results are robust to model specifications which address omitted variable bias both at individual- and school-level. One policy implication of our results is that desegregation policies which concentrated on the two per cent most segregated schools would probably improve school results and reduce ethnic inequality.Ethnic inequality; Immigrant schooling; Educational attainment; Contextual effects; Ethnic inequality; Immigrant schooling
Future of supply chain planning: Closing the gaps between practice and promise
The purpose is to develop a research agenda for supply chain planning (SCP) relevant to practice.
We critically evaluate academic literature on SCP in order to understand how problems are addressed in their particular context, what the outcomes are, and the mechanisms producing the observed outcomes. Four categories of SCP are studied: sales and operations planning (S&OP), supply chain master planning, supply chain materials management, and collaborative materials management. We introduce the concept of enabling mechanisms to identify specific innovations in materials management and production management that can facilitate the future improvement of SCP.
The critical evaluation of current SCP theory presents very limited results that are of practical relevance. SCP is not presented as an intervention and the results are not in a form that is actionable for practitioners. The body of literature is almost absent in addressing problems according to context, it presents limited evidence of intended outcomes, and it fails to identify unintended outcomes. As a consequence, research is unable to bolster theoretical understandings of how outcomes â both intended and unintended â are achieved. In our forward-looking research agenda we leverage our understanding of the enabling mechanisms in order to propose research to make mature S&OP and novel types of SCP implementable.
The paper is an example of a structured approach to developing a research agenda that is relevant to practice and can be used more widely in logistics and supply chain management.
This paper presents a research agenda to close the gap between practice and promise in SCP.
We operationalize what constitutes practical relevance for an established field of research
Estimating Social and Ethnic Inequality in School Surveys: Biases from Child Misreporting and Parent Nonresponse
We study the biases that arise in estimates of social inequalities in childrenâs cognitive ability test scores due to (i) childrenâs misreporting of socio-economic origin and (ii) parentsâ nonresponse. Unlike most previous studies, we are able to draw on linked register data with high reliability and almost no missingness and thereby jointly consider the impact of measurement error and nonresponse. Using data on 14-year-olds (nâ=â18,716) from a new survey conducted in England, Germany, the Netherlands, and Sweden (Children of Immigrants Longitudinal Survey in Four European Countries), we find that child reports on parental occupation are well aligned with parentsâ reports in all countries, but reports on parental education less so. This leads to underestimation of socio-economic disparities when child reports of education are used, but not occupation. Selective nonresponse among parents turns out to be a real problem, resulting in similar underestimation. We also investigate conditional estimates of immigrantânon-immigrant disparities, which are surprisingly little affected by measurement error or nonresponse in socio-economic control variables. We conclude that school-based surveys on teenagers are well advised to include questions on parental occupation, while the costs for carrying out parental questionnaires may outweigh the gains
Nordic research in logistics and supply chain management: an empirical analysis
Purpose â The purpose of this data-based analysis is to report and reflect on the characteristics of
the academic discipline concerned with logistics and supply chain management (SCM) as it is
conducted in the Nordic countries (Denmark, Finland, Iceland, Norway and Sweden). The paper
further seeks to explain variations in the research field in terms of the demographics, research domains
and methodologies, and publication patterns of the studyâs respondents.
Design/methodology/approach â An e-mail questionnaire survey was distributed to 353
researchers based in the Nordic countries. With 144 answers returned, the response rate was 41 per cent.
Findings â The study did not provide a clear picture of a distinct Nordic research paradigm applying
to the study of logistics and SCM. The analysis shows as characteristic of research issues pursued by
Nordic researchers the focus on supply chains and networks and the use of dyads, chains or networks
of organizations as levels of analysis. The use of case study methodology and a highly diversified
publication pattern were likewise evident. Most researchers were found to rely heavily on external
research funding. Significant differences were also identified for research conducted by researchers
holding PhD degrees as compared to research by respondents with lower degrees, for researchers
affiliated with institutions based in the technical sciences in comparison to those in the social sciences,
and for institutions according to their varying degrees of experience with research in the field and
external funding.
Research limitations/implications â The research reported here may help individual researchers
raise their consciousness about their own research.
Originality/value â This is the first empirical study to analyze research paradigms within logistics
and SCM in the Nordic countries. It identifies a number of significant differences in regard to research
patterns among various categories of researchers and institutions
Reconsidering Res Judicata: A Comparative Perspective
We aimed to prospectively investigate the paternal antigen-induced cytokine secretion by peripheral blood mononuclear cells (PBMCs) in response to hormone treatment in women undergoing in vitro fertilisation (IVF) and to examine the predictive value of the cytokine secretion profile in the outcome of IVF treatment, in a pilot study. Twenty-five women were included and IVF treatment was successful for six and unsuccessful for 19 women. Blood samples were collected before IVF treatment, on four occasions during IVF and four weeks after embryo transfer. The numbers of Th1-, Th2- and Th17-associated cytokine-secreting cells and cytokine levels in cell supernatants were analysed by enzyme-linked immunospot-forming (ELISpot), enzyme-linked immune-sorbent (ELISA) or Luminex assay. None of the cytokines (IFN-Îł, IL-4, IL-5, IL-10, IL-12, IL-13, IL-17, TNF and GM-CSF) had any predictive value regarding IVF outcome. The majority of the cytokines reached their peak levels at ovum pick-up, suggesting an enhancing influence of the hormonal stimulation. Pregnancy was associated with a high number of IL-4-, IL-5- and IL-13-secreting cells four weeks after ET. In conclusion, the results do not support our hypothesis of a more pronounced peripheral Th1 and Th17 deviation towards paternal antigens in infertile women with an unsuccessful IVF outcome, although this is based on a small number of observations. A larger study is required to confirm this conclusion. Higher numbers of Th2-associated cytokine-secreting cells in pregnant women four weeks after ET do corroborate the hypothesis of a Th2 deviation during pregnancy
Estimating non-marginal willingness to pay for railway noise abatement: Application of the two-step hedonic regression technique
Estimating non-marginal willingness to pay for railway noise abatement: Application of the two-step hedonic regression technique
In this study we estimate the demand for peace and quiet, and thus also the willingness to pay\ud
for railway noise abatement, based on both steps of the hedonic model regression on property prices.\ud
The estimated demand relationship suggests welfare gains for a 1 dB reduction of railway noise as;\ud
USD 162 per individual per year at the baseline noise level of 71 dB, and USD 86 at the baseline\ud
noise level of 61 dB. Below a noise level of 49.1 dB, individuals have no willingness to pay for railway\ud
noise abatement. Our results also show the risk of using benefit transfer, i.e. we show empirically\ud
that the estimated implicit price for peace and quiet differs substantially across the housing markets.\ud
From a policy perspective our results are useful, not only for benefit-cost analysis, but also as the\ud
monetary component on infrastructure use charges that internalize the noise externality
Estimating non-marginal willingness to pay for railway noise abatement: Application of the two-step hedonic regression technique
In this study we estimate the demand for peace and quiet, and thus also the willingness to pay
for railway noise abatement, based on both steps of the hedonic model regression on property prices.
The estimated demand relationship suggests welfare gains for a 1 dB reduction of railway noise as;
USD 162 per individual per year at the baseline noise level of 71 dB, and USD 86 at the baseline
noise level of 61 dB. Below a noise level of 49.1 dB, individuals have no willingness to pay for railway
noise abatement. Our results also show the risk of using benefit transfer, i.e. we show empirically
that the estimated implicit price for peace and quiet differs substantially across the housing markets.
From a policy perspective our results are useful, not only for benefit-cost analysis, but also as the
monetary component on infrastructure use charges that internalize the noise externality
Additive Manufacturing of Slow-Moving Automotive Spare Parts: A Supply Chain Cost Assessment
This study develops a cost model for the additive manufacturing (AM)-produced spare parts supply chain in the automotive industry. Moreover, we evaluate the economic feasibility of AM for slow-moving automotive spare parts by comparing the costs of the traditional manufacturing (TM) spare parts supply chain (SPSC) with centralized, outsourced AM SPSC. Data from a multiple case study of an OEM in the automotive industry regarding SPSC is utilized. The supply chain costs of 14 individual spare parts were analyzed, and the total SPSC cost for the AM and TM, were compared. Three of the fourteen parts showed potential for cost-savings, if they were produced with AM instead of TM. In this context, AM polymer parts showed greater potential than metal to replace TM as the more economical option of manufacturing from a total supply chain cost perspective. This study shows that the AM competitiveness to TM, from a financial perspective, increases for spare parts with low demand, high minimum order quantity, and high TM production price. The SPSC cost model included: cost of production, transport, warehousing, and service costs. This study contributes to the emerging field of part identification for AM and the existing literature regarding cost modeling in SPSCs
Terminology for analytical capillary electromigration techniques (IUPAC Recommendations 2003)
This paper presents terms and definitions for capillary electromigration
techniques for separation, qualitative and quantitative analysis and physico-chemical
characterization. Names and descriptions for such techniques (e.g., capillary
electrophoresis and capillary electrochromatography) as well as terms for the phenomenon
of electroosmotic flow are included
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