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Using an increasing returns specification for distribution, an inverted U pattern between the share of distribution in gross domestic product and the level of development is shown to arise. A cross-section time-series data set is constructed and merged with one used to analyze the service sector. In contrast to the rising pattern found for services, an average time-series relation that exhibits an inverted U pattern is established. The empirical results are robust, for example, to choice of functional form and country and time period coverage. A similar pattern is found in the average cross-section (country) relation between distribution and development.  相似文献   
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In September 2001, the Danish Ministry of Foreign Affairs commissioned a study of the present and potential links between migration and development. In January 2002, the new Danish Government announced a decision to enhance the links between its aid and refugee policies as part of the overall focus on poverty reduction. The present paper provides a state–of–the–art overview of current thinking and available evidence on the migration–development nexus, including the role of aid in migrant–producing areas. It offers evidence and conclusions around the following four critical issues: Poverty and migration People in developing countries require resources and connections to engage in international migration. There is no direct link between poverty, economic development, population growth, and social and political change on the one hand, and international migration on the other. Poverty reduction is not in itself a migration–reducing strategy. Conflicts, refugees, and migration Violent conflicts produce displaced persons, migrants, and refugees. People on the move may contribute both to conflict prevention and reconciliation, and to sustained conflicts. Most refugees do not have the resources to move beyond neighbouring areas, that is, they remain internally displaced or move across borders to first countries of asylum within their region. Aid to developing countries receiving large inflows of refugees is poverty–oriented to the extent that these are poor countries, but it is uncertain what effect such aid has in terms of reducing the number of people seeking asylum in developed countries. Furthermore, such aid may attract refugees from adjacent countries experiencing war or political turmoil. Migrants as a development resource International liberalization has gone far with respect to capital, goods and services, but not to labour. International political–economic regimes provide neither space nor initiatives for negotiations on labour mobility and the flow of remittances. There is a pressing need to reinforce the image of migrants as a development resource. Remittances are double the size of aid and target the poor at least as well; migrant diasporas are engaged in transnational practices with direct effects on aid and development; developed countries recognize their dependence on immigrant labour; and policies on development aid, humanitarian relief, migration, and refugee protection are internally inconsistent and occasionally contradictory. Aid and migration Aid policies face a critical challenge to balance a focus on poverty reduction with mitigating the conditions that produce refugees, while also interacting constructively with migrant diasporas and their transnational practices. The current emphasis on aid selectivity tends to allocate development aid to the well performing countries, and humanitarian assistance to the crisis countries and trouble spots. However, development aid is more effective than humanitarian assistance in preventing violent conflicts, promoting reconciliation and democratization, and encouraging poverty–reducing development investments by migrant diasporas. The paper is a synthesis of current knowledge of migration–development dynamics, including an assessment of the intended and unintended consequences of development and humanitarian policy interventions. We examine whether recent developments in the sphere of international migration provide evidence of a “crisis”, as well as the connections between migration, globalization, and the changing nature of conflicts. We summarize current thinking on the main issues at stake and examine available evidence on the relations between migration and development. Then the consequent challenges to the aid community, including the current debates about coherence and selectivity in aid and relief are discussed and, finally, we elaborate on the four conclusions of the overview.  相似文献   
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The authors present three educational approaches designed to demystify the writing process and to support better writing skills among family therapists. One framework is an academic course in professional writing, another is a writing seminar for family therapy and physician trainees within a medical school setting, and the third is a 2-hour continuing education writing workshop for family therapists. Each is replicable within a variety of settings.  相似文献   
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This paper describes the design optimization of a robot sensor used for locating 3-D objects employing the Taguchi method in a computer simulation scenario. The location information from the sensor is to be utilized to control the movements of an industrial robot in a 'pick-and-place' or assembly operation. The Taguchi method, which is based on the Analysis-of-Variance (ANOVA) approach, is utilized to improve the performance of the sensor over a wider operating range. A review of the Taguchi method is presented along with step-by-step implementation details to identify and optimize the design parameters of the sensor. The method allows us to gauge the impact of various interactions present in the sensor system exclusively and permits us to single out those factors that have a dominant influence on the overall performance of the sensor. The investigation suggests that the Taguchi method is a more structured and efficient approach for achieving a robust design compared with the classical full factorial design approach.  相似文献   
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Many recent papers have used semiparametric methods, especially the log-periodogram regression, to detect and estimate long memory in the volatility of asset returns. In these papers, the volatility is proxied by measures such as squared, log-squared, and absolute returns. While the evidence for the existence of long memory is strong using any of these measures, the actual long memory parameter estimates can be sensitive to which measure is used. In Monte-Carlo simulations, I find that if the data is conditionally leptokurtic, the log-periodogram regression estimator using squared returns has a large downward bias, which is avoided by using other volatility measures. In United States stock return data, I find that squared returns give much lower estimates of the long memory parameter than the alternative volatility measures, which is consistent with the simulation results. I conclude that researchers should avoid using the squared returns in the semiparametric estimation of long memory volatility dependencies.  相似文献   
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The last observation carried forward (LOCF) approach is commonly utilized to handle missing values in the primary analysis of clinical trials. However, recent evidence suggests that likelihood‐based analyses developed under the missing at random (MAR) framework are sensible alternatives. The objective of this study was to assess the Type I error rates from a likelihood‐based MAR approach – mixed‐model repeated measures (MMRM) – compared with LOCF when estimating treatment contrasts for mean change from baseline to endpoint (Δ). Data emulating neuropsychiatric clinical trials were simulated in a 4 × 4 factorial arrangement of scenarios, using four patterns of mean changes over time and four strategies for deleting data to generate subject dropout via an MAR mechanism. In data with no dropout, estimates of Δ and SEΔ from MMRM and LOCF were identical. In data with dropout, the Type I error rates (averaged across all scenarios) for MMRM and LOCF were 5.49% and 16.76%, respectively. In 11 of the 16 scenarios, the Type I error rate from MMRM was at least 1.00% closer to the expected rate of 5.00% than the corresponding rate from LOCF. In no scenario did LOCF yield a Type I error rate that was at least 1.00% closer to the expected rate than the corresponding rate from MMRM. The average estimate of SEΔ from MMRM was greater in data with dropout than in complete data, whereas the average estimate of SEΔ from LOCF was smaller in data with dropout than in complete data, suggesting that standard errors from MMRM better reflected the uncertainty in the data. The results from this investigation support those from previous studies, which found that MMRM provided reasonable control of Type I error even in the presence of MNAR missingness. No universally best approach to analysis of longitudinal data exists. However, likelihood‐based MAR approaches have been shown to perform well in a variety of situations and are a sensible alternative to the LOCF approach. MNAR methods can be used within a sensitivity analysis framework to test the potential presence and impact of MNAR data, thereby assessing robustness of results from an MAR method. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
20.
K. Goda  H. P. Hong 《Risk analysis》2008,28(2):523-537
Seismic risk can be reduced by implementing newly developed seismic provisions in design codes. Furthermore, financial protection or enhanced utility and happiness for stakeholders could be gained through the purchase of earthquake insurance. If this is not so, there would be no market for such insurance. However, perceived benefit associated with insurance is not universally shared by stakeholders partly due to their diverse risk attitudes. This study investigates the implied seismic design preference with insurance options for decisionmakers of bounded rationality whose preferences could be adequately represented by the cumulative prospect theory (CPT). The investigation is focused on assessing the sensitivity of the implied seismic design preference with insurance options to model parameters of the CPT and to fair and unfair insurance arrangements. Numerical results suggest that human cognitive limitation and risk perception can affect the implied seismic design preference by the CPT significantly. The mandatory purchase of fair insurance will lead the implied seismic design preference to the optimum design level that is dictated by the minimum expected lifecycle cost rule. Unfair insurance decreases the expected gain as well as its associated variability, which is preferred by risk-averse decisionmakers. The obtained results of the implied preference for the combination of the seismic design level and insurance option suggest that property owners, financial institutions, and municipalities can take advantage of affordable insurance to establish successful seismic risk management strategies.  相似文献   
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