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21.
Water quality trading (WQT) is a market arrangement in which a point-source water polluter pays farmers to implement conservation practices and claims the resulting benefits as credits toward meeting a pollution permit. Success rates of WQT programs nationwide are highly variable. Most of the literature on WQT is from an economic perspective emphasizing property rights, transaction costs, and the role of the price signal, but this institutional approach cannot fully account for the differential success rates between and within WQT programs. In this paper I turn to the role of social embeddedness and trust in helping explain these variable outcomes. Using interview data from all WQT programs nationwide I demonstrate that differential success rates between, and particularly within programs is largely determined by the presence or absence of a trusted local intermediary with relationships to the farming community. Trust helps WQT programs succeed because it makes information more credible to farmers, makes outreach to farmers more efficient, and buffers the risk that farmers may perceive in participating in the trading scheme.  相似文献   
22.
As the civil law expression of internet plus transactions, the legal relations in online trading platform transactions constitute a complex aggregate of legal relationships composed of groups of legal relations. Specifically, they consist of three basic interlinked legal relationships: Contract relations for online trading platform services between the platform provider and the seller or service provider, and between the platform provider and the consumer. This includes the sales or service contract relations between the triad of the seller, the service provider and the consumer. These relations contain five kinds of major content, viz., the provision of transaction space, the publishing of transaction information, price escrow payment, distribution and delivery of the commodity, and transaction credit evaluation. They involve three forms of supplementary legal relations: the supplementary contract relationship between the platform provider and a third party payment institution; between the seller and third party credit reporting agency; and between the seller and a logistics enterprise. The three forms of supplementary contractual legal relations are set up to act on the major contents of the basic legal relationships in online transactions. On the basis of the online trading platform service contract relationships between the platform provider and the triad of the seller, the service provider and the consumer, the flow of the above- mentioned legal relations centers on the contract of sales or service set up between the seller, the service provider and the consumer to accomplish the aim of the online transaction, meet social needs and boost economic development.  相似文献   
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In this paper, we consider the problem of estimating the Laplace transform of volatility within a fixed time interval [0,T] using high‐frequency sampling, where we assume that the discretized observations of the latent process are contaminated by microstructure noise. We use the pre‐averaging approach to deal with the effect of microstructure noise. Under the high‐frequency scenario, we obtain a consistent estimator whose convergence rate is , which is known as the optimal convergence rate of the estimation of integrated volatility functionals under the presence of microstructure noise. The related central limit theorem is established. The simulation studies justify the finite‐sample performance of the proposed estimator.  相似文献   
25.
生态文明建设是一项系统工程,需要通过整体推进,构筑规划、建设、管理、技术、产业、社会和合作协同发展的综合体系。未来上海应以建立和完善市场机制为核心,以法律机制为前提,以政府监管机制为保障,以能力建设机制为基础,以社会参与机制为监督,按照"引逼结合、多方合力、突出重点、先行先试"的原则,加快上海生态文明建设机制创新。主要途径有:完善碳排放交易试点,建立长效市场机制;推进分布式能源应用,提高清洁能源比重;加快新能源汽车推广,优化交通能源结构;培育发展再制造产业,推广先进制造理念。  相似文献   
26.
We propose localized spectral estimators for the quadratic covariation and the spot covolatility of diffusion processes, which are observed discretely with additive observation noise. The appropriate estimation for time‐varying volatilities is based on an asymptotic equivalence of the underlying statistical model to a white‐noise model with correlation and volatility processes being constant over small time intervals. The asymptotic equivalence of the continuous‐time and discrete‐time experiments is proved by a construction with linear interpolation in one direction and local means for the other. The new estimator outperforms earlier non‐parametric methods in the literature for the considered model. We investigate its finite sample size characteristics in simulations and draw a comparison between various proposed methods.  相似文献   
27.
金融危机近些年爆发频繁,传统市场理论如有效市场假说和行为金融面对复杂的现实金融世界未能给出合理解释.Lo提出的适应性市场假说则弥合了这两个学派的分歧,逐渐引起了学术界的重视.本文尝试从动态市场效率、时变贝塔和技术交易策略演变这三个角度对适应性市场假说能否解释我国资本市场进行实证研究.研究发现:我国股票市场效率在动态变化,无效的时段与金融危机或政策巨变等重大事件联系密切;股市风格指数贝塔随市场环境变化而改变;技术交易策略绩效随投资者适应环境变化而演变.研究结果表明,适应性市场假说相比有效市场假说和经典资本资产定价模型,能够更好地解释我国资本市场上述现象.最后对投资者如何根据市场环境变化制定适应性投资策略给出几点建议.  相似文献   
28.
本文应用Berry等(1995)[2]提出的离散选择需求模型和差异产品的伯川德竞争模型,并利用淘宝网上的交易数据,对声誉、消费者保障计划、保修服务及信息披露四种信号策略在网上交易中的作用进行了实证研究。需求估计结果表明消费者保障计划中的"7天无理由退换货"计划以及保修服务可以作为产品质量的信号;而在其他有效信号策略存在的情况下,消费者保障计划中的"先行赔付"计划以及卖家声誉作为质量信号的作用则被削弱。成本分析表明,信息披露虽然可以提高消费者购买的可能性,但是由于发出信号的成本太低,容易被低质量卖家所模仿,因此并不能作为有效的质量信号。本文首次从供给和需求两个方面分析了信号机制在信息不对称情况下的效应及其作用机制。  相似文献   
29.
在碳排放约束下,利用动态古诺模型,分析厂商如何优化产量、交易碳排放权的规模、净化节约额以实现利润最大化的问题,得到相应的均衡量和各阶段最优量,并给出竞争市场中的企业减排策略以及政府的行为和碳排放权价格对企业减排策略的影响,阐述在竞争市场中减排和碳排放权交易的运行机制。研究发现: 双寡头竞争市场中存在均衡状态;在减排率较低时,制造上获得最高利润,而企业追求过高的减排率将会导致过分依赖碳减排市场而获得较低的利润;制造商应该适时低价购入过量碳排放权,而在高价时卖出多余的碳排放权,以充分利用碳排放权市场以增加利润降低成本;制造商的利润会随着政府碳排放权分配系数的增加而增加。  相似文献   
30.
晚清时期,受鸦片暴利的驱使,四川省广种鸦片,川土的销售和消费都很旺盛,烟土税也成为全省重要的财政来源之一.但旺盛的鸦片生产和贸易严重干扰了人们的正常生产和生活秩序,引起了乡村地区生产结构的巨大变动,使经济与社会发展更趋畸形,因而四川也成为了禁烟的重点省份.经过几届政府官吏的努力,四川省的鸦片在清朝覆灭前几乎禁绝,有力地维护了社会正义,但也使当时一些农民的生计受到影响.  相似文献   
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