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81.
This study uses employment data to examine why some industries host more new high-growth firms than others. Using a unique data base of 201 industries over a 15-year period, we find that increases in the proportion of employment of scientists and engineers in industries are positively associated with counts of fast-growing new firms; however, we do not detect a relationship between fluctuations in the proportion of employment in sales and production occupations and counts of fast-growing new firms. The findings suggest that technological innovation is an important determinant of entrepreneurial opportunity. Further, they suggest that private new firms are an important means of organizing commercial innovation and that new firms may be less constrained by complementary assets than has been previously understood.  相似文献   
82.
Given the marked heterogeneous conditions in smallholder agriculture in Sub-Saharan Africa, there is a growing policy interest in site-specific extension advice and the use of digital extension tools to provide site-specific information. Empirical ex-ante studies on the design of digital extension tools and their use are rare. Using data from a choice experiment in Nigeria, we elicit and analyze the preferences of extension agents for major design features of ICT-enabled decision support tools (DSTs) aimed at site-specific nutrient management extension advice. We estimate different models, including mixed logit, latent class and attribute non-attendance models. We find that extension agents are generally willing to use such DSTs and prefer a DST with a more user-friendly interface that requires less time to generate results. We also find that preferences are heterogeneous: some extension agents care more about the effectiveness-related features of DSTs, such as information accuracy and level of detail, while others prioritise practical features, such as tool platform, language and interface ease-of-use. Recognising and accommodating such preference differences may facilitate the adoption of DSTs by extension agents and thus enhance the scope for such tools to impact the agricultural production decisions of farmers.  相似文献   
83.
A double hurdle statistical analysis of 250 farms in the Tigray region of Ethiopia reveals different causal factors for soil conservation adoption versus intensity of use. Farmers' reasons for adopting soil conservation measures vary sharply between stone terraces and soil bunds. Long‐term investments in stone terraces were associated with secure land tenure, labour availability, proximity to the farmstead and learning opportunities via the existence of local food‐for‐work (FFW) projects. By contrast, short‐term investments in soil bunds were strongly linked to insecure land tenure and the absence of local food‐for‐work projects. Public conservation campaigns on private plots reduced adoption of both stone terraces and soil bunds. Whereas capacity factors largely influenced the adoption decision, expected returns carried more influence for the intensity of stone terrace adoption (measured as metres of terrace per hectare). More stone terracing was built where fertile but erodible silty soils in higher rainfall areas offered valuable yield benefits. Intensity of terracing was also greater in remote villages where limited off‐farm employment opportunities reduced construction costs. These results highlight the importance of the right kind of public interventions. Direct public involvement in constructing soil conservation structures on private lands appears to undermine incentives for private conservation investments. When done on public lands, however, public conservation activities may encourage private soil conservation by example. Secure land tenure rights clearly reinforce private incentives to make long‐term investments in soil conservation.  相似文献   
84.
Fertilizer Demand in China's Reforming Economy   总被引:5,自引:0,他引:5  
  相似文献   
85.
推广转基因抗虫棉对次要害虫农药施用的影响分析   总被引:3,自引:0,他引:3  
本研究的主要目的是分析在转基因抗虫棉有效控制棉花主要害虫(棉铃虫)、减少农药施用之后,可能导致的对棉花次要害虫的影响。通过多年的棉农生产跟踪调查和计量模型分析,研究结果表明,近年来棉农用来控制次要害虫的农药施用量有所增加,应引起有关部门的重视,但它的农药施用量远远小于采用转基因抗虫棉后整体减少施用的农药量;研究还发现,转基因抗虫棉在控制主要害虫农药施用量的减少,不是导致次要害虫农药施用量增加的主要原因,它仅仅能解释次要害虫农药施用增加量的一小部分。  相似文献   
86.
Recent policy from the European Union has attempted to justify social tourism initiatives on the basis that they lead to a more sustainable tourism industry. However, the majority of latest research in the field has been focused on the benefits for participants, with the addition of some evidence on the economic impacts of such programmes on destinations, which have pointed towards sustainability outcomes including: a longer tourism season, more even spread of demand, and longer periods of employment for tourism workers. Yet there is a lack of direct evidence linking such programme to these outcomes. This paper aimed to explore this important disconnect between policy assumptions and evidence-based outcomes through an analysis of the deseasonalising effects of the Spanish social tourism programme for older people. The research found that this programme does have an effect on the seasonal nature of employment and economic activity in most regions studied, but that the huge volume of demand from international tourists in the high seasons masks the quantitative effects in the regions with the highest seasonal concentration of international tourists. Recommendations for policy and practice in sustainable tourism are made that are transferable to many countries and regions that adopt social tourism programmes.  相似文献   
87.
Conventional wisdom holds that in markets with positive feedbacks being first to market can matter more than product quality. In this paper, we test that intuition within a generalized Pólya urn model. We find that if we assume constant feedbacks, in the long run, higher quality products dominate the market regardless of initial market shares, contradicting the common wisdom. However, when we allow for variable feedbacks, initial advantages persist almost indefinitely. Thus, the choice of whether to rush to market or focus on quality depends on market characteristics such as whether the positive feedbacks result from more consistent returns to scale or from more variable social influences.  相似文献   
88.
A recent study by Fitza argued that the prior estimates of the Chief Executive Officer (CEO) effect are conflated with events outside the CEO's control, are largely the result of random chance, and that the true CEO effect is smaller than has been previously estimated. We suggest that the empirical methodology employed by Fitza to support these claims substantially overstates the “random chance” element of the CEO effect. We replicate Fitza's findings, highlight methodological issues, offer alternative conclusions, and using multilevel modeling (MLM), suggest that his analyses mischaracterize the CEO effect. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
89.
This paper examines how environmental resources and costs feature in business models of small- and medium-sized tourism enterprises (SMTEs). Several studies have pointed to the generally positive nature of the relationship between the economic and environmental performance of tourism firms. Yet, although business models act as a vector between these aspects of firm performance, they have been overlooked in sustainable tourism discourse. The paper reports findings from discussion groups of SMTE businesses in South West England during the global economic downturn. Environmental costs and cost control were afforded relatively little importance in terms of value creation; conversely, there was a strong and predictable emphasis on revenue generation. Indirect tactics emerged for dealing with guests’ environmental behaviours which reflected this prevailing commercial logic. Green credentials were routinely de-emphasized, sometimes regarded as liabilities, in a form of greenhushing. Responses were framed by reference to social media and how online reviews may negatively impact on future value capture. Conceptually, the business model emerged as an important lens for understanding how environmental resources and costs were valourized. The paper highlights the need to ensure that contemporary approaches to environmental management in SMTEs reflect the current and fast-changing conditions that frame business models.  相似文献   
90.
Footnote 19 of the landmark U.S. antitrust decision in Continental T.V. v. GTE Sylvania, Inc. 433 U.S. 36 (1977) declares that “Interbrand competition … is the primary concern of antitrust law.” We trace the antecedents and influence of this declaration, argue that it is inappropriate, and conclude that it should be abandoned.  相似文献   
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