上市公司竞争优势持续期实证研究评价

竞争优势持续期(简称CAP)是指公司新投资项目收益率超过资本成本的持续时间。根据有限增长期股利贴现模型推理的竞争优势持续期模型为投资者提供了比较行业内上市公司竞争优势情况、判断上市公司股票投资价值的独特视角和分析工具。     

多基站分布式协作中有效反馈机制与误差分析

在分析一种多基站分布式协作下行传输系统结构及其信号传输特性基础上,研究了 多基站分布式下行协作中利用信道时间相关性的低速率有效反馈机制,并给 出了基于量化码本空间码字索引重排获得一新码本的构造与实现算法。此外,还讨论了反馈 误差对系统性能的影响。通过性能分析可知,相对于多基站集中调度协作系统而言,基于有 效反馈机制的多基站分布式协作模式所引起的系统性能损失在低误比特率时并不明显,且可 通过适当的码本优化设计以及反馈误差保护措施进一步减小反馈误差对系统性能的影响。     

城市特殊生境绿化技术研究——以上海 20年的研究成果为例

城市里大量的不透水面引发绿地空间严重缩水、 热岛效应加剧、城市雨洪频发等一系列严重的城市环境问 题。解决人口密度大、绿化用地少与高质量实现扩绿增绿、 实现城市居民对美好生活向往的矛盾，成为城市生态建设和 环境提升的核心难题，开展路面、屋面、墙面及桥柱等城市 特殊生境绿化成为城市高质量发展和城市品质提升的关键抓 手。以上海为例，总结了近20年来城市特殊生境绿化的研 究进展，围绕植物、介质、模块和管护四要素，从生境的特 殊性、适生植物种质创新和定向筛选、生境重建、一体化技 术、低维护管理及功能评价等方面取得了系列理论积淀和技 术创新，实践了有限空间的持续生长理念，形成完整的特殊 生境绿化技术体系，为公园城市建设发挥重要支撑作用。     

R&D contribution in TFP growth of Greek industry: A limited information likelihood approach

We provide a novel panel model to decompose total factor productivity (TFP) growth in the Greek industry at the firm level while we tackle the contribution of R&D. We, therefore, opt for parametric methodology that provides statistical inference and would validate the results. Our modeling departs from prior strong assumptions such as error terms across firms being independent. In fact, we provide a novel limited information maximum likelihood (LIML) estimation method that adequately deals with the issue of endogeneity and model misspecification. We demonstrate that our model detects variability in terms of TFP growth components across industries and firms. Our results show that R&D would enhance TFP of Greek firms, albeit the crisis has had a detrimental impact. Financial ratios such as liquidity and solvency ratios also affect TFP as we demonstrate that both would enhance TFP. The solvency ratio is important as it provides an estimate of whether the firm can cope with debt. We also note variability across small versus medium and large firms and report that small firms are more productive and spend more of their revenues on R&D. In terms of policy, our evidence warrants higher R&D spending to enhance TFP growth, though R&D funding is a concern.     

The equilibrium of the bargaining game and core convergence theorem on an exchange economy with limited traders

Debreu and Scarf (1963), Hildenbrand (1974), Aumann (1964), Dierker (1975), Bewley (1973), and others have shown that the core of an exchange economy with infinitely many or finitely many traders converges. However, an exchange economy does not always consist of infinitely many or finitely many traders. This note provides proof of the core convergence theorem on an exchange economy with limited traders by a bargaining game methodology. The main contribution of this note is to innovate the equilibrium solution to the bargaining game in the exchange economy. In this note, the concept of common payoff is introduced; in the bargaining game of a coalition on its common payoff, all coalition members will get the same distribution, thus the distribution scheme of the cooperation surplus of the exchange economy is determined. This note shows that the bargaining game among the traders on the distribution of the cooperation surplus will make the pure exchange economy with limited traders converge to the Walrasian equilibrium, all the allocations other than the Walrasian equilibrium will be eliminated from the core of this economy.     

网络沟通对股票市场的影响--基于投资者有限关注视角的研究

本文通过雪球网数据构建投资者网络沟通质量指标,并结合分析师预测特色数据,实证检验投资者网络沟通行为对股价同步性及特质性波动的影响。研究发现:网络沟通与股价同步性之间呈U形非线性关系,而与股价的特质性波动呈正相关;分析师预测特色数据通过投资者网络沟通行为进入股票市场,其中网络沟通质量与分析师乐观度的交互项同股价同步性呈负相关,而与股票特质性波动呈正相关。进一步细分市场发现,投资者网络沟通在牛市和熊市中对于股价同步性及特质性波动的影响是非对称的。     

化工企业所涉及有限空间作业的安全管控思路

文章结合自身从事化工企业安全管理的现场工作经验,学习和接触到的管理思路和方法,以及对目前有限空间作业安全管理的新规定,结合对国务院安委会印发的《全国安全生产专项整治三年行动计划》的认识和思考,从有限空间作业基本原则,作业前的风险分析,易出现的有限空间管理问题,管理程序措施以及应急救援入手,梳理化工企业有限空间作业安全管控思路。