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21.
科技服务业产出测算是对科技服务业产出数据的统计与分析,加强科技服务业产出数据的规范统计和应用分析可为我国政府调整产业政策提供重要数据支撑。以科技服务业产出测算为研究对象,结合学者观点、国家标准及各级政府相关产业政策,提出将分支产业作为初始指标的横向统计思路,构建科技服务业产出测算指标体系。在数据收集方面,强调要做好“收”与“填”两个基本工作;在指标确立和数据收集基础上,进一步提出未来预测的两种方法,以此作为科技服务业产出数据预测的初步探索;提出应从统一数据统计标准、完善数据调查与公开制度、加强数据资源开发3个方面建立健全我国科技服务业产出数据测量与管理体制机制。 相似文献
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We explore the innovation performance benefits of alliances for spin-off firms, in particular spin-offs either from other firms or from public research organizations. During the early years of the emerging combinatorial chemistry industry, the industry on which our empirical analysis focuses, spin-offs engaged in alliances with large and established partners, partners of similar type and size, and with public research organizations, often for different reasons. We seek to understand to what extent alliances of spin-offs with other firms (either large- or small- and medium-sized firms) affected their innovation performance and also how this performance may have been affected by their corporate or public research background. We find evidence that in general alliances of spin-offs with other firms, in particular alliances with large firms, increased their innovation performance. Corporate spin-offs that formed alliances with other firms outperformed public research spin-offs with such alliances. This suggests that, in terms of their innovation performance, corporate spin-offs that engaged in alliances with other firms seemed to have benefitted from their prior corporate background. Interestingly, it turns out that the negative impact of alliances on the innovation performance of public research spin-offs was largely affected by their alliances with small- and medium-sized firms. 相似文献
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This paper studies the expansion of an option price (with bounded Lipschitz payoff) in a stochastic volatility model including a local volatility component. The stochastic volatility is a square root process, which is widely used for modeling the behavior of the variance process (Heston model). The local volatility part is of general form, requiring only appropriate growth and boundedness assumptions. We rigorously establish tight error estimates of our expansions, using Malliavin calculus. The error analysis, which requires a careful treatment because of the lack of weak differentiability of the model, is interesting on its own. Moreover, in the particular case of call–put options, we also provide expansions of the Black–Scholes implied volatility that allow to obtain very simple formulas that are fast to compute compared to the Monte Carlo approach and maintain a very competitive accuracy. 相似文献
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Studies that simultaneously explore the effects of sensory experience on consumer emotions and behavior are rare. This paper builds a model of buying behavior based on sensory experience, 570 valid questionnaires were obtained from coffeehouse customers. Using structural equation modeling and multiple regression analysis, this paper validates the concept model and verifies that sensory experience is a significant antecedent to buying behavior. This study indicates that certain sensory experiences significantly influence emotion. Emotion also plays a mediating role in the relationship between sensory experience and behavioral intentions. The findings are theoretically and practically profound as they address the relationships among sensory experience, consumer emotions, behavioral intentions, and buying behavior, as well as explore how the five senses affect emotions and buying behavior. This paper concludes by indicating managerial implications and research limitations. 相似文献
28.
Farmers in the Vietnamese Mekong Delta face a wide range of climate-related and hydrological factors which threaten rice production. Smallholder farmers must adapt to climate change to sustain rice production as their central and most important livelihood activity. A sample was stratified across agro-ecological areas in the Delta affected by flooding, alluvial soils, acid sulphate soils, and saline water intrusion and by derived farmer typologies. A rural livelihoods approach was used in focus group discussions and in-depth interviews to identify and enumerate enabling and constraining adaptation factors. Smallholders experienced diverse natural hazards such as floods, abnormal rains, high temperatures, water scarcity, and salinity intrusion specific to the agro-ecological areas. Adaptation was constrained by labour shortages, water quality, topography, access to combine harvesters, transportation infrastructure, dryers and household savings. Adaptation was enabled by farming techniques and experience, cooperative groups, water quantity, access to information, and ability to purchase agro-chemicals through credit. Small farmers (< 1?ha) were more constrained than large farmers (> 1?ha) who had an expanded livelihood asset base. A range of policy implications are discussed, but adaptation is not just about technological fixes but requires overall improvements in a range of human, social and financial components. 相似文献
29.
Michal Kvasnička Rostislav Staněk Ondřej Krčál 《Journal of Industry, Competition and Trade》2018,18(1):47-58
This paper studies the effect of station density on prices in the retail gasoline market in the Czech Republic. We estimate the impact of the number of competing stations in various driving-distance ranges around each station on prices. We find that station density has a negative effect on prices; the effect decreases with distance and is statistically significant up to six kilometers. This suggests that the retail gasoline market is local rather than national. 相似文献
30.
This paper examines the international trade of a variety of genetically modified (GM) food products over a 27-year period (1984–2011) with data from the United Nations using the tools of social network analysis. The results indicate that each of the different crops have a distinctive pattern of trade that has changed over time due to a number of different factors. Also, trade in agricultural commodities became more diversified over time, dominated less by the United States and other nations central in the trade networks and trade in the individual GM crops was stable over time. Countries maintained their trading partners for specific crops, despite the adoption of the genetically modified varieties. The economic implications of these results are discussed for specific countries. 相似文献