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41.
Linear and nonlinear Granger causality tests are used to examine the dynamic relation between daily Dow Jones stock returns and percentage changes in New York Stock Exchange trading volume. We find evidence of significant bidirectional nonlinear causality between returns and volume. We also examine whether the nonlinear causality from volume to returns can be explained by volume serving as a proxy for information flow in the stochastic process generating stock return variance as suggested by Clark's (1973) latent common-factor model. After controlling for volatility persistence in returns, we continue to find evidence of nonlinear causality from volume to returns.  相似文献   
42.
Futures research includes the problem of generating reasonably exhaustive and plausible scenarios for a given topic, a problem for which there are no truly satisfactory solutions. This article reviews and evaluates a method, field anomaly relaxation, first put forward some 20 years ago. The evaluation is in the context of an illustrative study of political developments in Europe. The research reconstructs and further develops the method and concludes that it has something to offer for scenario generation. Its weaknesses are identified and suggestions for further research are made.  相似文献   
43.
This paper compares the approximation capabilities of the minflex-Laurents translog and minflex generalized Leontief cost functions with their translog and generalized Leontief counterparts in Monte Carlo experiments. The minflex Laurent specifications generally provided closer approximations to underlying technical and economic parameters. Imposition of nonlinear restrictions on some of the parameters of the minflex Laurent models yielded measurable improvement in estimated elasticities of substitutions, returns to scale, and rates of technical change.The refereeing process of this paper was handled through E. Appelbaum.  相似文献   
44.
The study examines the origins of technology important to improving productivity in the food-processing industries. Technology flows were measured both by patents in patent classes closely identified with six food industries, and by a sample of significant food-processing innovations. These data are consistent with the hypothesis that interindustry technology flows are the most significant determinant of productivity improvements in the food industries. These findings solve the enigma that the food-processing industries have enjoyed rapid improvements in productivity despite making very modest investments in research and development.  相似文献   
45.
This paper considers the impact of Programa de Educación, Salud y Alimentación ( PROGRESA ), a large Mexican rural anti-poverty programme that had an evaluation sample in which overall treatment was randomly assigned to some communities but not others, on child nutrition. When we examine the impact of PROGRESA based on the presumption of randomized allocations, we find that PROGRESA had no or even a negative impact on child nutrition. However, not all children designated to receive nutritional supplements actually did so. Our preferred estimates – child fixed-effects estimates that control for unobserved heterogeneity that is correlated with access to the supplement – indicate a significantly positive and fairly substantial programme effect of the nutritional supplements on children 12–36 months. They imply an increase of about a sixth in mean growth per year for these children and a lower probability of stunting. Effects are somewhat larger for children from poorer communities but whose mothers are functionally literate. The long-term consequences of these improvements are non-trivial; its impact working through adult height alone could result in a 2.9% increase in lifetime earnings.  相似文献   
46.
The Australian hospital industry is described and it is noted that the term ‘hospital’ is applied to a wide range of institutions. The main problems and issues associated with hospitals are discussed, including the lack of adequate methods of measuring their ‘products’ and of allocating funds to them. The role of the medical staff in influencing the ‘demand’ for hospital beds and in resource allocation is emphasised as a major influence on hospital behaviour. In a study of the determinants of the costs of Victorian public hospitals it was found that the complexity of the case-mix as measured by diagnosis related groups (DRGs) was a major determinant of teaching hospital costs but not of those of other large hospitals. DRG-based funding and costing of hospitals is recommended as a strategy for achieving increased efficiency.  相似文献   
47.
Abstract.  This paper is concerned with the sustainability of free‐trade agreements (FTA). FTA sustainability is influenced by governments' valuations of political contributions, discount factors, the lobbying position of the specific‐interest groups in the intra‐industry trade sectors, and the sectoral coverage of the FTA. I find that (i) under certain conditions, the FTA under protectionist lobbying could be more sustainable than the FTA under no political pressure; (ii) the lobby‐supported FTA is more sustainable than the lobby‐opposed FTA and the FTA under no political pressure; and (iii) multisector trade enhances FTA sustainability. JEL Classification: F12, F13, F15.  相似文献   
48.
The paper highlights the main drivers for merger policy reform in the European Union, including the consequences of the recent appeal court reverses. It discusses some of the substantive and procedural issues that the reform package should address, and outlines the reforms in progress. The author concludes that much of the reform package will be beneficial, but some important opportunities have been missed in this inevitably patchwork process.  相似文献   
49.
While folklore in finance holds that split valuation effectsare due to dividend increases associated with splits, littleis known about magnitudes of dividend and nondividend componentsof split announcement effects. We find that splits and dividendsare indeed informational substitutes, a notion we characterizemore precisely, but a significant portion of split valuationeffects, 46% according to our estimates, cannot be attributedto dividend information in splits. Our techniques extend theliterature on conditional event-study methods and we illustratetheir practical value in testing hypotheses and analyzing datanot amenable to analysis by standard procedures.  相似文献   
50.
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