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一种构建CORBA Trader服务集群的方法 被引量:1
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作者 窦文 贾焰 邹鹏 《电子学报》 EI CAS CSCD 北大核心 2003年第5期641-644,共4页
OMG的Trader服务是分布对象的“中介”服务 ,在大规模分布环境下 ,对Trader服务的需求日益显得迫切 .单一节点的Trader服务其本身会变成分布应用的性能瓶颈 .本文提出了一种基于一致性Hash方法的Cache节点定位算法和TraderCache集群框... OMG的Trader服务是分布对象的“中介”服务 ,在大规模分布环境下 ,对Trader服务的需求日益显得迫切 .单一节点的Trader服务其本身会变成分布应用的性能瓶颈 .本文提出了一种基于一致性Hash方法的Cache节点定位算法和TraderCache集群框架 ,并对该框架的负载均衡能力和请求响应能力进行了测试 . 展开更多
关键词 CORBA trader服务 集群 一致性hssh
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OMG Trader服务的软件过程模型
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作者 鲍敢峰 敖青云 +1 位作者 董歆奕 尤晋元 《计算机工程与设计》 CSCD 北大核心 1999年第5期34-37,共4页
软件分产品和过程两方面。过程模型在软件开发中有重要的应用价值。结合面向对象开发方法学和工具,提出一种软件过程的Petri网模型。该模型适合描述软件开发中不断变化和不完整的过程,在OMGTrader服务的开发过程中取得很好的效果。
关键词 软件过程 PETRI网 trader服务 软件开发
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Effect of Trader Composition on Stock Market
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作者 王茂基 王兴元 刘真真 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第5期925-930,共6页
In this study, we build a double auction market model, which contains two types of agent traders, i.e., the noise traders and fundamentalists, to investigate the effect of the trader composition on the stock market. I... In this study, we build a double auction market model, which contains two types of agent traders, i.e., the noise traders and fundamentalists, to investigate the effect of the trader composition on the stock market. It is found that, the non-trivial Hurst exponent and the fat-tailed distribution of transaction prices can be observed at any ratio of the noise traders. Analyses on the price variation properties, including the Hurst exponent and the price variation region, show that these properties are stable when the ratio is moderate. However, the non-price variation properties, including the trading volume and the profitability of the two kinds of agents, do not keep stable untrivially in any interval of the ratio of noise traders. 展开更多
关键词 AGENT double auction the trader composition non-price variation properties
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Challenges Facing Zimbabwean Cross Border Traders Trading in South Africa: A Review of Literature
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作者 Norman Chiliya Reginald Masocha Stanislous Zindiye 《Chinese Business Review》 2012年第6期564-570,共7页
Cross border traders make a major contribution to the growth of economies in Southern Africa. Cross border trade is a source of livelihood for many poor people, especially women. However, few studies examined challeng... Cross border traders make a major contribution to the growth of economies in Southern Africa. Cross border trade is a source of livelihood for many poor people, especially women. However, few studies examined challenges facing cross border traders and future business prospects.The aim of this paper is to examine the challenges that face Zimbabwean cross border traders in South Africa. The paper goes further to review existing literature as well as empirical studies in order to identify the major challenges that face Zimbabwean cross border traders. Among the challenges noted are crime, harassment due to xenophobia, traders are often stigmatized as "prostitutes" or "smugglers", accommodation problems, extortion and bribery by the South African Police and municipal police officials, delays at the border post during peak periods and banks that close early and also do not operate on Sundays. The Zimbabwean Cross Border Traders Association should build office in Musina and Johannesburg so that members can easily consult with the association in times of problems and also help with marketing information like distribution of brochures showcasing Zimbabwean products sold by cross border traders and also organize fairs where Zimbabwean traders can display their products. Furthermore cases of harassment by police officials should be investigated and dealt with. Banks that do have branches at the border posts are also urged to provide 24 hour service to cross border traders. 展开更多
关键词 cross border traders CHALLENGES regional trade BORDER exchange GOODS
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On the Edge of Malfeasance: Informal African Immigrant Traders in the/ohannesburg Inner City, South Africa
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作者 Inocent Moyo Trynos Gumbob 《Sociology Study》 2014年第4期323-333,共11页
Admittedly, the stratospheric rise of Informal African Immigrant Traders (IAIT) in the Johannesburg inner city within a climate of discrimination, harassment, hostility, and xenophobia has engendered survival strate... Admittedly, the stratospheric rise of Informal African Immigrant Traders (IAIT) in the Johannesburg inner city within a climate of discrimination, harassment, hostility, and xenophobia has engendered survival strategies which border on the illegal and underground. Based on an in-depth interview study of 40 IAIT, operating in the Johannesburg inner city and specialising in clothes, cellphone and accessories, household goods, fruits and vegetables, and a courier company, this paper posits that the registered and unregistered IAIT operate side by side with the latter operating from undesignated sites, either bribing or deceitful evading the Johannesburg Metropolitan Police (JMP). Is this the characteristic of IAIT in the Johannesburg inner city? Ostensibly, the success of challenging the institutional regulatory regime points to the possibility of African immigrant traders existing on the edge of impropriety or lawlessness. To this end, there is a need for comprehensive policy initiatives starting from the national and cascading to the provincial and municipality levels that will effectively address and manage urban informality, including the activities of the IAIT, failing which these will fuel operations outside the regulatory regimes and the mushrooming of the underground economic activities. 展开更多
关键词 African immigrant traders urban informality discrimination JOHANNESBURG South Africa
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《WALL STREET TRADER 2000》过把炒股瘾
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作者 游侠 《广东电脑与电讯》 2000年第4期110-110,共1页
股票热潮 相信读者们在日常生活中,都曾经听到又或是接触过股票,近日来香港又或是全球各地正兴起炒买科技股,如果大家对炒买股票有浓厚兴趣又或者想学习现实股票市场的炒买技巧,相信《WALLSTREET TRADER 2000》这游戏可以给大家一个不... 股票热潮 相信读者们在日常生活中,都曾经听到又或是接触过股票,近日来香港又或是全球各地正兴起炒买科技股,如果大家对炒买股票有浓厚兴趣又或者想学习现实股票市场的炒买技巧,相信《WALLSTREET TRADER 2000》这游戏可以给大家一个不错的体验! 展开更多
关键词 WALLSTREET trader2000 电脑游戏
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Examining the Views and Opinions of Itinerary Traders on Adherence to COVID-19 Lockdown in Enugu State,Nigeria
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作者 Ugochukwu Simeon Asogwa Benjamin Okorie Ajah +3 位作者 John Thompson Okpa Ikenga Patrick Ugwu Rebecca Ginikanwa Nnamani Albert Okorie 《Fudan Journal of the Humanities and Social Sciences》 2023年第3期411-434,共24页
The outbreak of COVID-19 caused human activities to be affected in one way or another.As a result,measures were put in place by various national governments to reduce the spread of the virus.This paper examines adhere... The outbreak of COVID-19 caused human activities to be affected in one way or another.As a result,measures were put in place by various national governments to reduce the spread of the virus.This paper examines adherence to COVID-19 guidelines in Nigeria among itinerant traders,using a total of 40 eligible participants from selected local governments in Enugu state,Nigeria.The study adapted purposive sampling techniques to identify eligible participants;while in-depth interview was the method used for data collection.Among other findings,result shows that the control measures rolled out by government were seriously undermined.Nomadic traders,driven by economic gains,played covert role in the spread of the virus.This signalled a weak link in the efforts to curb the spread of the virus in Nigeria.The study contributes to a more exact diagnosis of the weak link in the efforts to contain the spread of the virus and how the quest for economic gains drove the abuse of COVID-19 mitigation protocols with its attendant health implications.It therefore recommends that government should strengthen the institutional capacity for detection and control,and provide the critical infrastructural facilities that will make for intensified surveillance in future epidemic or pandemic outbreak.Economic incentives and the effective monitoring of protocol enforcers saddled with the responsibility of enforcing government directives are also encouraged in order to curb compromise. 展开更多
关键词 COVID-19 Interstate movement Community transmission Itinerant traders Compliance
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数字经济助推贸易强国建设:逻辑、困境与破解之道 被引量:2
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作者 程时雄 陈琬怡 《国际贸易》 北大核心 2024年第5期5-14,共10页
数字经济具有数字产业化、产业数字化、数据价值化以及数字化治理的特征,有助于赋予贸易强国建设新动能和新优势。从微观层面看,数字经济以新产品赋能贸易规模、外贸结构;从中观层面看,数字经济以新模式推动产业升级;从宏观层面看,数字... 数字经济具有数字产业化、产业数字化、数据价值化以及数字化治理的特征,有助于赋予贸易强国建设新动能和新优势。从微观层面看,数字经济以新产品赋能贸易规模、外贸结构;从中观层面看,数字经济以新模式推动产业升级;从宏观层面看,数字经济给国家提供新平台促进外贸提质增效。但是,在赋能发展过程中,在数字化基础设施配备、产品贸易结构、数字核心技术研发、数字治理失灵、数字贸易规则制定等方面存在一定的困境。为此,中国应完善数字基础保障建设、拓展数字中间品贸易、加快突破核心数字技术、健全数字贸易治理监管体系、深化数字贸易规则衔接及国际合作,从而以数字经济助推贸易强国建设,实现高水平对外开放和高质量发展。 展开更多
关键词 数字经济 贸易强国 高水平对外开放 高质量发展
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以高水平对外开放推动贸易强国建设:内在逻辑、赋能渠道与实践路径
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作者 马林静 齐冠钧 梁明 《国际贸易》 北大核心 2024年第8期17-26,96,共11页
实施高水平对外开放与推动贸易强国建设存在历史契合性和实践必然性。高水平对外开放赋能贸易强国建设的渠道为:以开放式发展厚植贸易强国建设的要素基础;以开放新优势打造贸易强国建设新动能;以更高水平开放推动贸易结构更趋优化;以开... 实施高水平对外开放与推动贸易强国建设存在历史契合性和实践必然性。高水平对外开放赋能贸易强国建设的渠道为:以开放式发展厚植贸易强国建设的要素基础;以开放新优势打造贸易强国建设新动能;以更高水平开放推动贸易结构更趋优化;以开放促改革构筑贸易强国建设的制度保障;以开放之道引领创建普惠共享、互利共赢的国际环境。在明确赋能渠道的基础上,文章提出以高水平对外开放推动贸易强国建设的实践路径包括:推动深层次制度开放,形成以制度开放效应为核心的贸易强国建设新动能体系;推动内外开放联动发展,以高效畅通的国内国际双循环赋能贸易强国建设;实施更大范围对外开放,以多维度的开放势能优化对外贸易区域市场结构;积极主动参与全球经济治理,增强我国在国际经贸体系中的制度性权力,塑造贸易强国建设的良好国际环境。 展开更多
关键词 高水平对外开放 制度型开放 贸易高质量发展 贸易强国
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中国式现代化视域下的贸易强国建设
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作者 乔晓楠 范如杰 《国家现代化建设研究》 2024年第4期72-88,共17页
贸易强国建设是中国式现代化建设的重要内容。中国贸易强国建设要兼顾跨国投资、国际贸易以及储备资产的变化,结合国际收支进行优化调整,设计贸易强国建设的实施路径,逐步实现国际收支整体平衡、经常账户结构平衡以及贸易账户结构平衡... 贸易强国建设是中国式现代化建设的重要内容。中国贸易强国建设要兼顾跨国投资、国际贸易以及储备资产的变化,结合国际收支进行优化调整,设计贸易强国建设的实施路径,逐步实现国际收支整体平衡、经常账户结构平衡以及贸易账户结构平衡。在建设贸易强国的策略上,要发挥超大规模市场与强大生产能力的优势,提升国际循环质量;加强自主创新与绿色低碳转型,塑造国际贸易新优势;加速数字产业化与产业数字化,打造国际贸易新形态;构建东西互济的双向开放新格局,拓展国际贸易新空间;推进高水平对外开放与国际经济秩序改革,营造国际贸易新环境。 展开更多
关键词 中国式现代化 贸易强国建设 国际贸易 跨国投资 国际收支
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高水平对外开放背景下中国环境产品进口的环境效应研究
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作者 唐克 李杨 《河海大学学报(哲学社会科学版)》 北大核心 2024年第3期131-146,共16页
高水平对外开放背景下发展绿色贸易是我国经济转型升级和实现高质量发展的必然选择。作为绿色贸易的代表,环境产品贸易自由化作为实现可持续发展的重要路径已得到世界各国的普遍共识。我国作为世界贸易组织(World Trade Organization,W... 高水平对外开放背景下发展绿色贸易是我国经济转型升级和实现高质量发展的必然选择。作为绿色贸易的代表,环境产品贸易自由化作为实现可持续发展的重要路径已得到世界各国的普遍共识。我国作为世界贸易组织(World Trade Organization,WTO)主要成员,全程参与了《环境产品协定》谈判并积极发展环境产品进口贸易,环境产品进口呈现规模先增后减、结构不平衡、市场相对固定等特点。结合Grossman和Krueger的贸易与环境经典理论以及Antweiler等的一般均衡模型,从理论层面阐释环境产品进口影响企业污染排放的机制,并选取我国微观企业的面板数据,从实证层面考察环境产品进口的环境效应。研究发现:一是环境产品进口可以降低企业污染排放,进一步的机制检验结果表明,环境产品进口的规模效应增加了企业烟粉尘排放量,而技术效应降低了烟粉尘排放量,结构效应不显著。二是在环境产品细分中,资源管理类产品和清洁技术与产品的进口对企业烟粉尘排放量的减少作用明显,而污染管理类产品对于环境改善作用不显著。三是环境产品进口额的增加对国有企业、外资企业以及高污染行业烟粉尘排放量有明显的抑制作用,而对民营企业和非高污染行业没有显著影响。鉴于此,建议建设国际高标准经贸规则和制度体系;坚持高水平“引进来”,实施进口差异化战略;发挥好对外开放中政府与市场的作用,加快培育企业绿色技术创新能力;打造国际一流水平的营商环境;实施高质量发展战略推进贸易强国建设。 展开更多
关键词 高水平对外开放 绿色技术 营商环境 贸易强国 环境产品 进口效应 烟粉尘排放量
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基于熵值法的陕西省外贸高质量发展评价研究
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作者 尤帅 郑强 《对外经贸实务》 2024年第3期84-90,共7页
外贸高质量发展对建设贸易强国、贸易强省具有非常重要的意义,不同省份应根据自身实际情况设计推动外贸高质量发展的战略与行动方案。本文基于熵值法建立外贸高质量发展综合指标评价体系,对陕西省外贸发展状况进行了评价。研究发现:(1)2... 外贸高质量发展对建设贸易强国、贸易强省具有非常重要的意义,不同省份应根据自身实际情况设计推动外贸高质量发展的战略与行动方案。本文基于熵值法建立外贸高质量发展综合指标评价体系,对陕西省外贸发展状况进行了评价。研究发现:(1)2014—2022年,陕西外贸发展呈现出先上升再下降、后又提升的趋势;(2)虽然与中西部相比陕西外贸发展质量排名靠前,但在全国范围内仅处于中下游水平。这些结果表明,陕西省“双循环”相互促进的功能尚不显著,外贸发展质量有待提高。基于此,本文提出:应结合区位优势、产业结构特征与科教资源创新能力,充分发挥比较优势、激发和释放内需潜力、坚持新发展理念等战略措施,推动陕西外贸高质量发展。 展开更多
关键词 高质量发展 外贸强国 熵值法 陕西
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中国公募REITs市场价格与投资者结构研究——基于多主体建模的分析
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作者 顾宗源 《管理现代化》 北大核心 2024年第3期57-65,共9页
深入认识公募REITs市场运行规律,对实现中国金融高质量发展具有重要意义。通过构建包括基本面交易者、动量交易者和噪声交易者的多主体模型,并使用机器学习方法对20只REITs进行校准,模拟价格形成过程并分析交易者结构。结果显示,中国公... 深入认识公募REITs市场运行规律,对实现中国金融高质量发展具有重要意义。通过构建包括基本面交易者、动量交易者和噪声交易者的多主体模型,并使用机器学习方法对20只REITs进行校准,模拟价格形成过程并分析交易者结构。结果显示,中国公募REITs收益率序列具有厚尾分布、自相关、波动集聚等特征。模型能够很好地模拟REITs市场价格形成过程,对未来收益率具有一定预测性。在REITs市场中,基本面交易者占主导,动量交易者次之,噪声交易者影响力微弱。建议监管机构应密切监测市场波动与风险暴露,发挥多主体模型在决策中的作用,同时加强投资者教育,避免投资者过度追求短期利益。 展开更多
关键词 REITS 基本面交易者 动量交易者 噪声交易者 XGBoost
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明清海禁时期朝鲜华商贸易形态的历史嬗变
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作者 黄文波 《延边大学学报(社会科学版)》 2024年第2期33-41,150,151,共11页
明清海禁时期,朝鲜华商的商贸活动随着历史的演进出现了一些形态上的变化。首先是在海禁严厉时期,正常的朝鲜华商贸易形态较宋元时期极大地萎缩,出现了特殊的商贸活动和商人形态,如依托官方贸易的官宦商人、开展走私贸易的非法商人等。... 明清海禁时期,朝鲜华商的商贸活动随着历史的演进出现了一些形态上的变化。首先是在海禁严厉时期,正常的朝鲜华商贸易形态较宋元时期极大地萎缩,出现了特殊的商贸活动和商人形态,如依托官方贸易的官宦商人、开展走私贸易的非法商人等。其次是特殊的朝鲜华商贸易形态产生了反噬作用,促使明朝间断开放民间贸易、清朝完全开放边市贸易,在一定程度上又恢复了中朝之间正常的华商贸易形态。总的来说,朝鲜华商贸易形态的嬗变,与明清王朝的对外贸易政策密切相关。 展开更多
关键词 明清时期 海禁政策 朝鲜王朝 华商 贸易形态 嬗变
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The Evolution Dynamic and Long-Run Equilibrium in a Stock Market with Heterogeneous Traders
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作者 Pengju Zhao Wei Zhang Yumin Liu 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2020年第1期55-67,共13页
This paper uses ideas from biological evolution to analyze the evolution of the securities market in which rational and irrational traders coexist.A market evolutionary model is developed to describe the dynamic traje... This paper uses ideas from biological evolution to analyze the evolution of the securities market in which rational and irrational traders coexist.A market evolutionary model is developed to describe the dynamic trajectories of rational and irrational traders'wealth.The main question is,are irrational traders eliminated as the securities market evolves.The paper considers the impact of new entrants on the security market long-term equilibrium.In addition,it discusses the existence and uniqueness of the long-term equilibrium The paper finds that,under some market conditions,irrational traders could survive in the long run. 展开更多
关键词 Behavioral Finance IRRATIONAL traderS financial EVOLUTION theory random DYNAMIC system
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How do Normal Traders and Sharp Traders Make Profits in the Chinese Security Market?
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作者 Mingyang Zhang Juliang Zhang +1 位作者 TCECheng Guowei Hua 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2020年第2期203-234,共32页
In this paper,we consider the strategic interaction between the normal and sharp traders in a dynamic limit-order security market and its impact on the Chinese security market at different market volatility levels.We ... In this paper,we consider the strategic interaction between the normal and sharp traders in a dynamic limit-order security market and its impact on the Chinese security market at different market volatility levels.We find that when the proportion of sharp traders is less than a threshold in an orderdriven market,the sharp traders who submit limit orders will get more returns than the normal traders.The participation of sharp traders in the market can increase the total social welfare of all the traders.In addition,we show that:(1)when the market volatility level is generally low,the short-term sharp traders benefit from larger volatility;(2)when the market volatility level is generally high,the insider/cheating sharp traders with high-frequent trading rather than the short-term sharp traders benefit from extreme high volatility;(3)when the market volatility level is moderate,the sharp traders can increase market liquidity. 展开更多
关键词 SHARP trader ORDER-DRIVEN MARKET limit-order strategic interaction
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Noise Trader Model of Agricultural Product Prices: Evidence from the Chinese Garlic Market
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作者 Jingtao Yi Xiangdong Liu 《Frontiers of Business Research in China》 2014年第3期327-345,共19页
This paper explores the determinants of the abnormal and volatile fluctuations of China's agricultural product prices in recent years by examining the trading behavior of traders, especially that of irrational noise ... This paper explores the determinants of the abnormal and volatile fluctuations of China's agricultural product prices in recent years by examining the trading behavior of traders, especially that of irrational noise traders. We present an overlapping generations model of the garlic market in which noise traders with erroneous beliefs influence prices. Noise traders' beliefs create a risk in the price of agricultural products that deters rational arbitrageurs from aggressively betting against them through changing supplies in a way that enables prices to diverge significantly from fundamental values even in the absence of fundamental risk. We also show that asymmetry of supply information, low price elasticity of demand, speculative capital inflows, restricted distribution channels, distorted wholesale markets from the perspective of market mechanisms and low risk aversion, biased self-attribution, and projection bias from the perspective of investor psychology, all influence expectations of investors and increase the volatility of agricultural product prices. 展开更多
关键词 noise trader agricultural product price volatility distributionsystem
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Heterogeneous Traders, the Leverage Effect and Volatility of the Chinese P2P Market
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作者 Xing Fang Bo Wang +1 位作者 Lanbiao Liu Yong Song 《Journal of Management Science and Engineering》 2018年第1期39-57,共19页
The new financial industry represented by peer-to-peer lending has gradually become a new source of volatility due to the increasing complexity of the Chinese financial market.This volatility leads to greater risk to ... The new financial industry represented by peer-to-peer lending has gradually become a new source of volatility due to the increasing complexity of the Chinese financial market.This volatility leads to greater risk to P2P investors and has become the focus of the regulatory authorities in China.Based on the background data of the P2P platform,Honglingchuangtou,we use the factor analysis method to construct a platform volatility(PV)index and we construct an HAR model to study the heterogeneous traders and leverage effect in the Chinese P2P market.The empirical results show that there are both short-term and long-term heterogeneous traders in the Chinese P2P market and that long-term traders have the greatest impact on market volatility.Similar to traditional financial markets,the volatility of the P2P market also shows a leverage effect,which means that the negative volatility of trader actions should have a negative impact on market fluctuations.With regard to the leverage effect,the LHAR-PV model is superior because of a higher goodness of fit and a lower prediction error. 展开更多
关键词 P2P lending VOLATILITY Heterogeneous trader Leverage Effect HAR model
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Study on Herding Equilibrium of Irrational Informed Trader
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作者 Xintian Zhuang Jingjing Wen 《Journal of Systems Science and Information》 2007年第1期51-59,共9页
This paper studies the connection between the irrational behavior of traders and the herding equilibrium of informed traders in security market. At first, we set up the trading system on the condition of market maker,... This paper studies the connection between the irrational behavior of traders and the herding equilibrium of informed traders in security market. At first, we set up the trading system on the condition of market maker, establish a trading model of perfectly rational traders, and then define herding equilibrium. Second, we extend the model using two parameters, and find the critical points of irrational traders when they reach the herding equilibrium. The result indicates that herding never occurs in market if all the traders are perfectly rational. If consider their irrational factor, it maybe arouse herding. Besides, along with the number of traders who make the same trading strategies increasing, the two critical points show some rules. 展开更多
关键词 IRRATIONAL herding equilibrium informed trader
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欧盟法中数字服务合同的法律构造研究 被引量:3
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作者 易磊 《信息安全研究》 CSCD 2023年第1期79-86,共8页
随着数字化服务的普及,欧盟出台《数字内容和数字服务指令》以填补欧盟法中规制数字服务合同的法律漏洞.研究了该指令规制数字服务合同的主要内容,包括适用主体、调整对象、性质、对价、履行规范、消费者权益救济手段等,分析得出欧盟规... 随着数字化服务的普及,欧盟出台《数字内容和数字服务指令》以填补欧盟法中规制数字服务合同的法律漏洞.研究了该指令规制数字服务合同的主要内容,包括适用主体、调整对象、性质、对价、履行规范、消费者权益救济手段等,分析得出欧盟规制数字服务合同在整体上呈现节制特征,个人数据对价化的观点冲击了GDPR的规则体系的结论.基于上述分析,结合我国已有法律规定,提出了我国规范和解释数字服务合同的建议. 展开更多
关键词 数字服务合同 消费者 经营者 个人数据对价化 同意 事前预防
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