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81.
The lack of a validated measure of active–passive union participation and a dearth of research into the relationship between generational cohort and union participation challenge union leaders to develop policies and practices to facilitate union renewal. We address these issues by (a) developing a multidimensional measure of union participation that captures both active and passive components, (b) using structural equation modelling to validate the measure within a nomological framework, and (c) investigating the impact of generational cohort on all paths in our framework. Data from members of a large American union confirm that generational cohort influences how union members participate in their union. The two‐factor measure developed in this study facilitates research into antecedents and outcomes of passive and active union participation. Our findings should also prove useful to unions seeking to increase participation within their membership, academics researching unions and generational cohort, and human resource practitioners operating in unionised environments.  相似文献   
82.
Two-part models based on generalized linear models are widely used in insurance rate-making for predicting the expected loss. This paper explores an alternative method based on quantile regression which provides more information about the loss distribution and can be also used for insurance underwriting. Quantile regression allows estimating the aggregate claim cost quantiles of a policy given a number of covariates. To do so, a first stage is required, which involves fitting a logistic regression to estimate, for every policy, the probability of submitting at least one claim. The proposed methodology is illustrated using a portfolio of car insurance policies. This application shows that the results of the quantile regression are highly dependent on the claim probability estimates. The paper also examines an application of quantile regression to premium safety loading calculation, the so-called Quantile Premium Principle (QPP). We propose a premium calculation based on quantile regression which inherits the good properties of the quantiles. Using the same insurance portfolio data-set, we find that the QPP captures the riskiness of the policies better than the expected value premium principle.  相似文献   
83.
Using economic analysis to prioritise improvements in environmental conditions is particularly difficult when multiple benefits are involved. This includes ‘bundling’ issues in agricultural pollution management, where a change in management action or farming systems generates multiple improvements, such as reductions in more than one pollutant. In this study, we conceptualise and compare two different approaches to analysing cost‐effectiveness when varying bundles of benefits are generated for a single project investment. Each approach requires data to be transformed in some way to allow the analysis to proceed. The index approach requires the transformation on the benefits side so that the effects of multiple pollutant changes can be combined into a measure for each project which can then be compared to costs. By comparison, the disaggregation approach requires the transformation on the costs side where costs for each project have to be apportioned across the different pollutants involved. The paper provides novel insights with an application to agricultural water quality improvements into the Great Barrier Reef in Australia, demonstrating that while both approaches are effective in prioritising projects by cost‐effectiveness, the disaggregation approach provides more insightful results and values that may be relevant for use as upper value guidelines in future project selection.  相似文献   
84.
Limited opportunities for crop switching and lengthy preharvesting periods make the plantation sector particularly vulnerable to climate change. Surprisingly, however, the economic consequences of climate change on plantation crops are seldom analysed. Drawing on a unique primary panel data set from a representative cross section of 35 tea estates in Sri Lanka over the period 2002–2014, this study implements a structural model of estate profit maximisation to estimate the elasticity of labour demand with respect to different components of weather. Results indicate a negative relationship between labour demand and rainfall in the south‐west monsoon, the north‐east monsoon and the second inter‐monsoon. A positive relationship is found between labour demand and rainfall in the first inter‐monsoon. Overall, predicted changes in rainfall by 2050 are anticipated to reduce labour demand by approximately 1,175,000 person‐days per year across Sri Lanka's tea plantation sector. This is likely to have considerable social and welfare implications, particularly for the Indian Tamil women who comprise the majority of the sector's workforce.  相似文献   
85.
派河为巢湖一级支流,水质差,针对派河流域开展了多项研究,产生了多项清水廊道技术,尚缺乏有效的产业化推广模式,基于此,构建了多层次、多元化清水廊道技术产业推广模式(“2S”VIP)。该模式包括组织机构、运行机制、推广模式平台、保障措施等。其中清水廊道技术推广模式平台包括综合技术信息平台、综合服务平台、产业化推广平台,以综合技术信息平台为支撑,以互联网+、大数据等为手段,综合服务平台为依托,产业化推广平台实现技术与市场的衔接。在政府的引导和监督下,通过一系列保障措施使各平台能顺利运行,达到产、学、研、用的有机融合。  相似文献   
86.
[目的]科学合理的适宜性评价是确保耕地整理能够有效开展的前提条件,同时对于我国的耕地保护与粮食安全保障也具有极为重要的意义。[方法]该研究首先选取可以反映区域耕地整理适宜性的指标因子,然后参考胡学东提出的约束条件评价模型,引入区域生态安全和社会经济双重约束,对研究区域在双重约束下的耕地整理适宜性进行评价,并通过K-Means聚类法将研究区域的耕地整理适宜性分区进行合理划分。[结果]生态安全约束和社会经济约束对区域耕地整理适宜性水平具有重大影响,高生态安全约束与高社会经济约束会降低耕地整理的适宜性,低生态安全约束与低社会经济约束会提高耕地整理的适宜性。[结论]引入生态安全约束和社会经济约束后,可以在一定程度上反映山地区域在社会经济与生态安全双重约束状态下的耕地整理适宜性情况,耕地整理适宜性评价结果更加符合当地实际情况,约束条件评价模型可以更加合理准确地对处于约束条件下的耕地整理适宜性进行评价,是对耕地整理适宜性评价方法的丰富与完善。  相似文献   
87.
以长春市为研究对象,基于未来经济处于新常态的发展态势,构建包含水资源、社会、经济、生态环境4个子系统的评价指标体系,并确定各指标的评价等级标准;基于模糊数学理论以及层次分析法构建包括目标层、准则层、指标层的3层模糊综合评价模型,以2015年为现状水平年,应用模型对长春市水资源开发利用潜力进行综合评价。结果表明:长春市水资源开发利用程度处于中等偏上水平,各辖区水资源开发利用规模不平衡,可通过产业结构调整提高全市用水效率,为经济持续增长提供保障。  相似文献   
88.
Cooperatives are established to improve farmers' production conditions, to increase their bargaining power and to enable them to benefit from modern value chains. In China, farmers are members of a cooperative for multiple reasons. Little is known on whether and how cooperative membership affects farmers’ choice of marketing channels. This paper examines determinants of farmers’ choice of marketing channels, especially how cooperative membership impacts upon this choice. Our analysis is based on survey data collected in 2015 among 625 apple growing farm households in the provinces Shaanxi and Shandong. We employ endogenous switching probit models to deal with potential endogeneity of membership in estimating the determinants of marketing channel choices. We find that cooperative membership has a positive impact on selling to wholesalers and a negative impact on selling to small dealers, but no significant impact on selling to the cooperative itself. As products sold through cooperatives generally comply with relatively stringent food quality and safety standards, these results imply that policies promoting cooperative members to sell their products through cooperatives are likely to have a significant impact on food quality and food safety in China.  相似文献   
89.
For many years, it was believed that higher-performing e-government features would boost citizen use of e-services. However, this straightforward proposition had never been tested. Using a survey of over 28,000 citizens across 32 European countries, we examined the effect of e-government performance on citizen use. Theoretically, a better-designed and maintained government website should be used more, but it was reject by multilevel model estimates. We found that performance was negatively related to citizen use of e-information and e-services, while e-participation use was insignificant. The implications of our findings on future efforts to increase the uptake of e-government are also discussed.  相似文献   
90.
利用企业所得税分享改革构建强度倍差模型,使用1997—2012年全国地级市数据,检验了地方财政压力对于投资多样性的影响及相关传导机制。结果表明,地方财政压力不利于投资多样性的提高;在财政压力下,地方容易形成偏向房地产行业的投资倾向。然而,不同地区地方财政压力对投资结构的影响存在异质性。经济发展水平较低的地区在财政压力下更容易降低投资多样性;而经济发展水平高的地区应对财政压力时,更倾向于通过多元化投资的方式做大税基、减轻财政压力。优化分税制结构、建立地方性税种能缓解地方财政压力,对于改变地方“房地产集中型”投资结构有一定的积极作用。  相似文献   
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