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211.
This paper employs individual firm data in order to check the existence of industry-spatial effects alongside other microeconomic determinants of R&D investment. Spatial proximity is defined by a measure of firms’ industry distance based on trade intensity between sectors. The spatial model specified here refers to the combined spatial-autoregressive model with autoregressive disturbances. In modelling the outcome for each location as dependent on a weighted average of the outcomes of other locations, outcomes are determined simultaneously. The results of the spatial estimation suggest that in their R&D decision firms benefit from spillovers originating from neighbouring industries.  相似文献   
212.
Abstract

Opinions differ about whether family structure, especially fertility, should be considered endogenous in models of behavior in developing countries. Faced with a dearth of good instruments, mainstream researchers often urge working in reduced form and, therefore, losing variables of policy interest or limiting the type of questions they ask to those where good instruments are available. Rather than treating endogeneity as a yes or no characteristic, we suggest instead that researchers consider the likely magnitude of endogeneity bias before moving to reduced form. Facing a situation where endogeneity bias is often presented as a concern but where we expect little endogeneity bias, we tackle endogeneity using multiple econometric techniques not available to the average researcher. We find support for our hypothesis that little bias arises due to the assumption of exogeneity of recent fertility in a model of women's employment.  相似文献   
213.
This study uses GARCH-EVT-copula and ARMA-GARCH-EVT-copula models to perform out-of-sample forecasts and simulate one-day-ahead returns for ten stock indexes. We construct optimal portfolios based on the global minimum variance (GMV), minimum conditional value-at-risk (Min-CVaR) and certainty equivalence tangency (CET) criteria, and model the dependence structure between stock market returns by employing elliptical (Student-t and Gaussian) and Archimedean (Clayton, Frank and Gumbel) copulas. We analyze the performances of 288 risk modeling portfolio strategies using out-of-sample back-testing. Our main finding is that the CET portfolio, based on ARMA-GARCH-EVT-copula forecasts, outperforms the benchmark portfolio based on historical returns. The regression analyses show that GARCH-EVT forecasting models, which use Gaussian or Student-t copulas, are best at reducing the portfolio risk.  相似文献   
214.
It is a wide-held assumption that professional development and change within purchasing and supply management (PSM) organisations can be explained and guided by a maturity model. In this paper the guidance which the maturity model concept offers to understand a PSM organisation's performance is assessed. The methodology is based on the outcomes of a literature review of PSM maturity models, development of an organisational change framework and the learning from three qualitative case studies. An alternative understanding of the development of the PSM organisation is offered through an organisational change framework, composing 1) movement transitions, 2) scalability of change, 3) acceptability of change, and 4) the substantive element of change. The research found that extant PSM maturity models are too rigid for PSM managers to apply, and although maturity models are commonly accepted in PSM literature, in practice, they may produce the opposite effect of what is promised. The PSM maturity models suggest that their application will lead to increased status and influence of PSM within the organisation; expectations that may not be met. PSM organisations’ change processes are subjected to a range of situational and contextual power relations which must be considered in order to advance the specific PSM organisation roles and responsibilities.  相似文献   
215.
We develop methods for inference in nonparametric time-varying fixed effects panel data models that allow for locally stationary regressors and for the time series length T and cross-section size N both being large. We first develop a pooled nonparametric profile least squares dummy variable approach to estimate the nonparametric function, and establish the optimal convergence rate and asymptotic normality of the resultant estimator. We then propose a test statistic to check whether the bivariate nonparametric function is time-varying or the time effect is separable, and derive the asymptotic distribution of the proposed test statistic. We present several simulated examples and two real data analyses to illustrate the finite sample performance of the proposed methods.  相似文献   
216.
Regulators can utilize a number of alternative methodologies for comparing firm efficiency, but these approaches need to be robust to be accepted by stakeholders. This study evaluates the consistency of water-utility performance rankings for Peruvian water utilities. The results indicate that data envelopment analysis (DEA) and stochastic frontier analysis (SFA) yield similar rankings in this case. In addition, the techniques have comparable success for identifying the best and worst performing utilities. However, these rankings based on sophisticated statistical techniques are not highly correlated with those developed by the Peruvian water regulator (SUNASS). This result does not invalidate the performance rankings obtained by the regulator, since those rankings are based on more dimensions of utility performance. However, they illustrate the importance of developing sound techniques for identifying weak utilities. Improvements in sector performance require that benchmarking be given greater attention than in the past.  相似文献   
217.
The purpose of this article is to measure the efficiency of pharmaceutical firms and identify their determinants using Korean and American samples from 1992 to 2004. We document some stylized facts in the patterns and sources of efficiency change in Korean and American pharmaceutical firms. The evidence shows that ownership structure can substantially influence the efficiency of pharmaceutical firms. Especially, institutional ownership rate affects corporate efficiencies negatively, corroborating the myopic institutional investor hypothesis. The hypothesis is supported by both Korean and American samples. However, we find evidence that foreign ownership in Korea promotes efficiency of pharmaceutical firms. It is shown that R&D intensity is positively related to contemporaneous largest ownership rate and prior foreign ownership rate in Korean pharmaceutical firms. In contrast, little evidence is found on the relationship between ownership structure and R&D intensity in the American pharmaceutical industry. These empirical results are robust even after we check the causal links among efficiency, R&D and ownership.  相似文献   
218.
The objective of the present study is to analyse the causes of the growth of international agricultural and food trade in volume terms from 1951 to 2000. The results suggest that income growth has been the principal reason for this expansion, while exchange rate stability and the real price of agricultural products played only a minor role. Multilateral trade liberalization and trade costs, given their long-term stability, are not elements that could have stimulated their growth. Finally, the intensive liberalization of trade which took place in various economic regions, especially in Europe, became a key factor in promoting agricultural trade among the countries participating in regional trade agreements. The study results also indicate that the determinants of trade growth for these goods were different to those for other goods and other periods.  相似文献   
219.
剖析了富士康科技集团员工跳楼事件的本质,总结出富士康员工的心智模式并分析其成因,提出了完善富士康员工心智模式的五条通路,即培养员工良好的性格、建立有效的沟通渠道、拓展人才策略与晋升空间、推行员工援助计划和在实践中努力提升情商。  相似文献   
220.
John Rawls's A Theory of Justice is examined from the perspective of experimental methods in economics and complex adaptive systems simulations. This paper first discusses the justice principle selection process in Rawls's representation of it as a hypothetical experiment. This hypothetical experiment fails to satisfy reasonable experimental controls, particularly as reflects the conception of the individual it employs. The second section of the paper discusses the differences between Rawls's two conceptions of rational persons associated with his distinction between thin and full theories of the good. The third section uses his fuller conception of rational persons, life plans, and psychological laws in the third part of the book to offer an alternative view of the selection process understood as a complex adaptive system. The fourth section turns to a topic raised by this complex system approach, the status of normative reasoning in political-economic systems. The fifth section summarizes.  相似文献   
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