辽东湾沿海及内陆土地利用生态环境效应对比分析

以位于辽东湾北部的营口市和辽宁省内部的鞍山市为研究区,引用研究区土地利用图形数据,通过将景观斑块分类的方法,对辽东湾沿海及内陆城市的土地利用生态环境效应进行比较分析。结果表明:(1)辽东湾的优势景观为林地和旱地。(2)鞍山市的区域生态环境指数为0.43,营口市的区域生态环境指数为0.51。辽东湾沿海城市较内陆城市生态环境好。     

当前差别存款准备金政策的制约因素及对策

差别准备金动态调控政策是我国建立逆周期宏观审慎管理框架,防范金融机构系统性风险的重要举措。本文围绕宏观审慎管理念和差别化调控思路,结合淄博市法人金融机构的具体情况,分析了2011年差别准备金动态调控中遇到的机制障碍,就如何完善差别准备金动态调控工具提出了政策建议。     

The willingness to pay–willingness to accept gap: A failed replication of Plott and Zeiler

The well-known willingness to pay–willingness to accept (WTP–WTA) gap refers to the observation that individuals attach a higher value to objects they own (WTA) than to objects they do not own (WTP). We report on experiments to re-investigate the possibility that the WTP–WTA gap arises from subject misconceptions due to experimental procedures as suggested by Plott and Zeiler (2005). The contribution of this paper is two-fold: first, we attempt to replicate the findings by Plott and Zeiler that the WTP–WTA gap disappears when using procedures that are aimed at reducing misconceptions, such as extensive training and practice rounds for the BDM mechanism. However, we fail to do so as the WTP–WTA gap persists in the main task where subjects state their WTA or WTP for a mug. Second, we use the paid practice rounds to identify subjects without apparent misconceptions and find that also for those subjects who never make dominated choices in the lottery tasks, the WTP–WTA gap in the mug task exists. Thus, we find no evidence of the idea that subject misconceptions are the main source of the WTP–WTA gap.     

农业生态旅游对区域经济的贡献及影响研究——以武汉市黄陂区为研究对象

[目的]农业生态旅游的发展逐渐成为区域经济新的增长点,分析农业生态旅游对区域经济的贡献及负面影响,协调两者间的关系,对于区域经济可持续发展具有重要意义。[方法]文章通过文献查阅和数据调查法,以武汉市黄陂区为研究对象,分析其农业生态旅游对区域经济的贡献及负面影响。[结果]农业生态旅游对黄陂区域经济的贡献主要表现在有效地促进区域现代农业的发展、产业结构的调整、农民就业及国民经济的增长,然而也存在农业生态旅游投资大、农民获利不均等因素直接影响区域经济发展以及农业生态环境遭受破坏后间接影响区域经济发展等负面影响。因此政府有必要提前科学规划农业生态旅游,提供支持引导,培养和提高公民的生态环保意识,保障社会、经济和环境的协调发展。[结论]鉴于黄陂区农业生态旅游对区域经济的贡献高于负面影响,为进一步保障区域经济的可持续发展,建议综合协调各个方面,将负面影响降到最低,以其为推动今后社会主义新农村建设提供一定参考。     

Sunk costs and travel cancellation: Focusing on temporal cost

Tourism products differ from ordinary retail products in terms of the spatial and temporal separation between the purchase and experiencing the product. Despite its importance, temporal separation has not drawn much attention in tourism research. The main objective of this study is to understand the effects of temporal sunk costs on potential travelers' cancellation intentions, in addition to monetary sunk costs. The results of this study suggested the possibility that temporal costs can be converted into monetary costs, but the conversion relationship may not be linear. This study also indicated that travelers' intentions to cancel a travel product decreased as the temporal and monetary sunk costs increased. Further, prior experience moderated the relationship when temporal sunk costs were involved, suggesting that repeat visitors' intentions to cancel their reservations are more influenced by temporal sunk costs than first-time visitors. Further discussion and implications are provided in the main body of this paper.     

Oil price shocks and volatility spillovers in the Nigerian sovereign bond market

This paper investigates volatility spillover in the Nigerian sovereign bond market arising from oil price shocks, using Vector Autoregressive Moving Average ‐ Asymmetric Generalized Autoregressive Conditional Heteroscedasticity (VARMA‐AGARCH) model. The paper covers the period March 22, 2011 to April 14, 2016 and makes use of the daily data of the Nigerian Sovereign Bond, Brent oil and West Texas Intermediate (WTI), respectively. We endogenously and sequentially detect structural break points using the test of Bai and Perron (2003) framework. In order to accurately estimate the model, we modify it by incorporating the break points into the VARMA‐AGARCH model, a process which if ignored would lead to model misspecification. The results obtained demonstrate a significant cross‐market volatility transmission between oil and sovereign bond market with ample sensitivity to structural breaks. The study also computes optimum weight portfolio and hedge ratio both with and without structural breaks and results equally indicate sensitivity to structural breaks.     

菱角壳的化学成分和药理活性研究进展

近年来对菱角壳的研究主要分为化学成分和药理活性研究两个方面,其中化学成分方面的研究可以概括为生物碱、酚酸类、萜类和甾体、多糖类、黄酮类5个方面;药理活性方面的研究可以概括为抗癌活性、抗氧化活性、降低α-葡萄糖苷酶活性、保肝护肝活性、抗菌活性5个方面。目前在化学成分方面的研究较弱,从研究结果来看,没食子酸及其衍生物是菱角壳的主要药用成分。最后就菱角壳的开发利用提出了几点建议。     

Interaction between message framing and consumers’ prior subjective knowledge regarding food safety issues

This study analyzed the interaction between message frames and recipients’ prior knowledge. The hypothesis is that less prior consumer knowledge will result in a larger framing effect. That is, if the subjective knowledge of the public is low, then the controversy created by mass media regarding a specific food-related event will be larger. Empirical results show that message frame has an influence on college students’ purchasing intentions. College students showed distinct responses in purchasing intention based on different headlines and different amounts of information within articles. The results further suggest that the framing effect depends not only on message frames, but also on the prior knowledge of the message recipient. Those who have less knowledge have larger variation in their purchase intention when responding to different message frames. This suggests that people with less knowledge are more likely to panic due to mass media reports regarding a food hazard issue. More informed consumers have less dramatic responses to food safety issues compared to less informed people.     

我国耕地保护政策研究：基于背景、效果与未来趋势

［目的］我国耕地保护政策对保护耕地、保障粮食安全具有重要意义。研究我国耕地保护政策出台的背景及前后关系、相同政策在不同区域内的执行效果差异，能够为更针对性地提出政策建议提供参考。［方法］主要运用了资料分析和定性描述的方法，首先按照耕地保护政策内涵划分为5个阶段，其次从时间、空间两个尺度，判断了耕地保护政策的数量、质量保护效果差异，最后提出了未来政策出台的方向和趋势。［结果］时间尺度上：1986年、1997年、2004年出台的政策对耕地数量保护的成效明显； 2014—2016年耕地质量保护效果略优于2009—2014年； 目前数量保护成效较好，但质量保护远未达到要求。空间尺度上：耕地数量保护效果西部地区最好，东北地区次之，中部地区优于东部地区； 耕地质量保护效果中部地区最佳，东北地区次之，东部地区优于西部地区。［结论］未来政策可向规范补充耕地全国统筹、完善耕地质量保护法律体系、调动农户保护耕地积极性等方向发展。     

供应商集中、公司治理与企业价值 ——基于我国A股制造业上市公司数据

本文通过选取2010—2017年我国A股制造业上市公司的数据,先研究公司供应商集中对于公司价值的直接影响,结论显示公司供应商集中对于企业价值有着负面的影响;然后在进一步研究中,探究了公司治理相关因素以及面临的融资约束情况对于公司供应商集中与公司价值关系的调节作用。实证结果显示,产权性质以及董事会独立性会对两者的关系产生影响;股东间的相互关联以及对于高管薪酬激励都对公司供应商集中与公司价值的关系有着负向的调节作用。与此同时公司面临的融资约束越小,公司供应商集中对于公司价值的负面效应越弱;最后利用多重中介效应模型探究了供应商集中的作用机制。