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1.
基于标准金融理论与行为金融理论相结合的思想,力图刻画投资者情绪的生成机理。以引起投资者情绪变化的货币环境、市场收益、市场波动、相关资产收益等因素为起点,引入市场投资价值、市场预期两个中间变量,建立了包含直接和间接影响两类路径的投资者情绪生成概念模型。使用中国股市2014年7月1日至2017年3月31日间的667组日度数据,在VAR建模的基础上开展实证研究。实证结果表明市场收益对投资者情绪具有直接的正向影响,市场波动和相关资产收益两因素基于市场预期中介变量间接负向作用于投资者情绪,而修正后引入的经济周期波动变量可以基于市场投资价值中介变量对投资者情绪产生正向影响,并进一步发现了市场收益、市场投资价值与投资者情绪之间存在正反馈强化过程。研究揭示出了投资者情绪生成的影响因素体系及其实现路径,将该领域研究深入到机理分析层面,并从一个侧面佐证了中国股市过度投机行为的存在。  相似文献   
2.
自党的十八届五中全会提出坚持“以人民为中心的发展思想”以来,专家学者从价值意蕴、科学内涵、理论生成、与其他理论的关系,以及贯彻落实等方面进行了研究并取得丰富的研究成果。但目前的研究也存一些不足,未来研究应坚持问题导向,注重解决人民群众的实际问题;拓宽研究视野,增强研究深度和广度;加强对领导干部如何践行以人民为中心的发展思想的研究,使得以人民为中心的发展思想进头脑、促实践、出成效。  相似文献   
3.
BackgroundSupporting women to continue breastfeeding is a global challenge. The Milky Way Program is an effective face to face intervention to increase breastfeeding rates up to six months postpartum. The sustainability and access to the Milky Way Program could be enhanced by transforming it into a mobile application allowing women to access relevant information from their own place at a convenient time.AimTo explore the process of transforming the Milky Way Program into an acceptable and usable mobile health application.MethodStakeholders including multidisciplinary researchers and end-users designed the application based on the Milky Way Program by using Persuasive System Design principles. A mixed-method approach was used in the development and evaluation process. Seven women were recruited through convenience sampling to pilot test the application. The women’s feedback was collected through an online survey six weeks after birth and individual interviews at four months postpartum.FindingsWomen in the pilot study reported that the breastfeeding application was well designed, easy to use, interactive, reassuring and evidence-based with credible sources of information.ConclusionThe Persuasive System Design model combined with end-user engagement can feasibly inform the development of an acceptable and usable mobile health application for breastfeeding based on a proven clinical intervention. Further rigorous testing is required to evaluate the effectiveness of the application on breastfeeding initiation and duration.  相似文献   
4.
ABSTRACT

Correlated bilateral data arise from stratified studies involving paired body organs in a subject. When it is desirable to conduct inference on the scale of risk difference, one needs first to assess the assumption of homogeneity in risk differences across strata. For testing homogeneity of risk differences, we herein propose eight methods derived respectively from weighted-least-squares (WLS), the Mantel-Haenszel (MH) estimator, the WLS method in combination with inverse hyperbolic tangent transformation, and the test statistics based on their log-transformation, the modified Score test statistic and Likelihood ratio test statistic. Simulation results showed that four of the tests perform well in general, with the tests based on the WLS method and inverse hyperbolic tangent transformation always performing satisfactorily even under small sample size designs. The methods are illustrated with a dataset.  相似文献   
5.
Strong orthogonal arrays (SOAs) were recently introduced and studied as a class of space‐filling designs for computer experiments. An important problem that has not been addressed in the literature is that of design selection for such arrays. In this article, we conduct a systematic investigation into this problem, and we focus on the most useful SOA(n,m,4,2 + )s and SOA(n,m,4,2)s. This article first addresses the problem of design selection for SOAs of strength 2+ by examining their three‐dimensional projections. Both theoretical and computational results are presented. When SOAs of strength 2+ do not exist, we formulate a general framework for the selection of SOAs of strength 2 by looking at their two‐dimensional projections. The approach is fruitful, as it is applicable when SOAs of strength 2+ do not exist and it gives rise to them when they do. The Canadian Journal of Statistics 47: 302–314; 2019 © 2019 Statistical Society of Canada  相似文献   
6.
The case-cohort design is widely used as a means of reducing the cost in large cohort studies, especially when the disease rate is low and covariate measurements may be expensive, and has been discussed by many authors. In this paper, we discuss regression analysis of case-cohort studies that produce interval-censored failure time with dependent censoring, a situation for which there does not seem to exist an established approach. For inference, a sieve inverse probability weighting estimation procedure is developed with the use of Bernstein polynomials to approximate the unknown baseline cumulative hazard functions. The proposed estimators are shown to be consistent and the asymptotic normality of the resulting regression parameter estimators is established. A simulation study is conducted to assess the finite sample properties of the proposed approach and indicates that it works well in practical situations. The proposed method is applied to an HIV/AIDS case-cohort study that motivated this investigation.  相似文献   
7.
通过对抗性设计方法解决项目评审中的社会伦理问题,为专家、申请者、大众提供争论和表达异议的民主环境。项目自动评价平台完成民主环境的构建,呈现专家、申请者、平台的争胜性关系,揭示霸权,旨在重塑自由、平等、公平、正义、特权等的项目评审中的社会伦理。  相似文献   
8.
The paper examines to what extent a player's market value depends on his skills. Therefore, a data set covering 28 performance measures and the market values of about 493 players from 1. and 2. German Bundesliga is analysed. Applying robust analysis techniques, we are able to robustly estimate market values of soccer players. The results show (1) that there are significantly underrated and overrated players and (2) that a player's affiliation to a certain team may contribute to his market value. We conclude that a club's reputation affects the market values of its players and that star players are in tendency overrated.  相似文献   
9.
本文主要基于信号博弈的卖方欺诈行为进行研究,假设拍卖中可能存在欺诈型和诚实型两种卖家,其中欺诈行为有概率发生在第二价格拍卖中:欺诈型卖方冒充竞拍者递交仅次于最高价的报价从而获得额外收益。两种卖家根据各自效用选择拍卖形式:第一价格或者第二价格。而竞买者将卖者的选择作为信号,更新对卖方类型的判断,然后制定报价策略。这是一个买卖方信号交叉影响的过程。考虑到拍卖过程中买方价值相关性,本文在建立模型中参考了关联价值原理。针对该模型进行分析,得出了不同情况下的买卖方策略,并且研究了买方报价、买方判断、卖方收益三者之间的关系。文中利用贝叶斯公式对双方的策略选择问题进行预测,与单纯的概率分布方法相比,更具实践价值。  相似文献   
10.
Hybrid organizational forms that combine commercial and welfare institutional logics play an increasingly important role in addressing the grand societal challenges we face today. Building on the literatures on hybrid organizations and social business models, we explore the characteristics of social businesses from a business model perspective. This study seeks to better understand the particularities and value drivers of hybrid social purpose in contrast to purely commercial business models. We follow a grounded theory approach and our findings are based on interview data from 17 social business firms. Building on social businesses' identified particularities, we propose four value drivers of social business models: 1) responsible efficiency, 2) impact complementarities, 3) shared values, and 4) integration novelties. We link our findings to the literature, contributing new insights into social businesses models and implications for practitioners.  相似文献   
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