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91.
The introduction of traffic management schemes has been one response of the National Parks to the problem of ever-increasing car-borne visitors and the consequent damage caused to the rural environment. By reviewing these schemes and by determining and explaining attitudes towards one particular traffic management experiment, the paper aims to deduce lessons for future policy. The analysis, based on two visitor surveys, suggests that the likelihood of success is improved when schemes are integrated, containing both ‘carrot’ and ‘stick’ elements. Since public perceptions are also found to be pivotal to its success, appropriate marketing of a scheme is vital. The paper concludes, however, that to achieve the fundamental objective of greater accessibility with less mobility, a more wide-ranging marketing effort is required intended to engender a sea change in attitude towards both the car and public transport. 相似文献
92.
93.
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
94.
This article investigates the change in operating performance of firms as they make the transition from private to public ownership. A significant decline in operating performance subsequent to the initial public offering (IPO) is found. Additionally, there is a significant positive relation between post-IPO operating performance and equity retention by the original entrepreneurs, but no relation between post-IPO operating performance and the level of initial underpricing. Post-issue declines in the market-to-book ratio, price/earnings ratio, and earnings per share are also documented. 相似文献
95.
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
96.
In many previous rice trade models, the commodity has been regarded as a homogeneous product. However, homogeneity is not an appropriate assumption, given the various types of rice that are traded and consumed. Parameters estimated from these models, therefore, do not reflect the real world market for rice and, hence, may mislead decision makers who use the results for policy evaluation purposes. This study uses an Armington approach to model the world rice trade as a differential good market and to derive trade elasticity parameters. 相似文献
97.
The value of a technology strategy has been increasingly discussed by R&D personnel and those involved in product development and business planning efforts. In this issue Albert Rubenstein and Americo Albala elevate this discussion by showing the importance of preparing a firm to compete by stressing the development of important, relevant technologies. Discovery and development must be channeled into areas that will be needed to support business initiatives likely to occur in the future. Albala stresses the importance of this change for the development of economies in nations that have been disappointed by the lack of success of importing technologies from more developed nations, while Rubenstein maintains that the pace of marketplace change requires a technology strategy in order to reduce the misapplication of scarce resources within the firm and the possibility of being blindsided by competitive developments. These essays continue a year-long series of contributions that the editor-in-chief solicited from members of the editorial board. Members were asked to reflect upon changes and opportunities that they see influencing our profession during the coming decade. Both of these short essays are designed to introduce new perspectives. It is not essential that you agree with the recommendations, but we hope that you are stimulated as you reflect on the issues they raise. 相似文献
98.
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
99.
Analyzing synthetic cohorts in the 1980 and 1990 Public Use Microdata Samples, we find that Mexican‐Americans and other Hispanics acquired English fluency at a faster pace than Puerto Ricans and Cuban‐Americans during the 1980s. Additional results indicate that English‐skill investments differently influenced the earnings distributions of these ethnic groups. 相似文献
100.
Intensive fertilizer use has led to nitrate contamination of groundwater in many areas. This article examines the possibility of removing nitrates through the construction of artificial wetlands. A pilot study conducted in Denmark has found that the method is effective and economical, at least for small waterworks, though further treatment is necessary before an acceptable microbiological water quality is attained. 相似文献