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61.
目的:探讨食管癌患者的健康相关生命质量现状及影响因素?方法:采用一般资料问卷?欧洲五维度健康评定量表(EQ-5D量表),对209例食管癌患者进行问卷调查,采用单因素分析和多因素分析探讨食管癌患者健康相关生命质量的影响因素? 结果:食管癌患者行动?自我照顾?日常活动?疼痛/不适?焦虑/抑郁五个维度存在问题的比例分别为18.2%?12.0%?22.0%?38.3%?25.4%;自评健康得分(VAS评分)为(75.20 ± 11.00)分;综合健康指数得分(Index得分)为(0.84 ± 0.22)分?患者的性别?家庭年收入?文化程度是VAS评分的主要影响因素;患者的年龄?治疗方式?肿瘤分期?医保类型是Index得分的主要影响因素?结论:实施心理干预?早诊早治?大病医疗保险有助于提高食管癌患者健康相关生命质量?  相似文献   
62.
采用2003-2012年中国除西藏外30个省市自治区的面板数据,考察信息通信技术渠道国际R & D溢出效应。运用面板单位根检验、协整检验、相关性分析、格兰杰因果检验、随机效应模型等计量方法,研究中国通过信息通信技术渠道获得的国际R & D溢出与当地全要素生产率之间的关系;建立Hansen非动态面板门槛模型,采用稳健标准差回归,检验各省份由信息通信技术渠道获得的国际R & D溢出门槛效应,并从产业转型升级和信息化建设角度分析存在门槛效应的原因。结果表明,中国大部分省份通过信息通信技术渠道获取的国际R & D溢出与全要素生产率有正相关关系;通过信息通信技术渠道获得的国际R & D溢出对当地技术进步的影响存在明显的地区差异和门槛效应。  相似文献   
63.
3D打印技术的发展使著作权法上的复制变得更为高效便捷,由此产生了一系列亟待梳理和解决的问题。基于3D打印技术原理,可将其分为输入和输出两个环节。在输入环节,对CAD文件的作品类型进行规制,采用视觉标准界定立体作品,并以“美术作品+模型作品”的思路进行综合保护;在输出环节,3D打印属于复制,且可以实现从平面到立体和从立体到立体的复制形态,复制权的控制范围应不限于现行法律所列举的方式。针对3D打印技术在网络传播中的侵权风险,应对合理使用中的私人复制予以限制,灵活运用“三步检验标准”对合理性进行审查。3D打印在著作权法方面并未引发新的法律问题,现行制度已存在包容空间,不必为其特设著作权新规,通过对现有规则的解释和借助已有案例的适用经验便能解决可预见的著作权法争端。  相似文献   
64.
65.
We use a large non-student sample to test how distinct measures of risk-attitudes relate to each other, to demographic characteristics and to real-life risk taking in the financial domain. These measures, namely the Bomb Risk Elicitation Task (BRET), self-reported willingness to take risks in general, the choice in a hypothetical lottery, the score in the Domain Specific Risk-Taking (DOSPERT) scale, appear to be positively correlated and exhibit a certain degree of consistency. Furthermore, a subset of these measures is driven by similar demographic characteristics as such that males are more risk seeking and risk-aversion increases with age. Using extensive data on the retirement portfolios of the participants during the years 2008–2014, we find that all of these measures are positively correlated with the riskiness of individual portfolios. The self-reported willingness to take risks in general appears to be the most relevant measure in predicting actual risk-taking behavior.  相似文献   
66.
John F.McLennan is well known for introducing the terms of “exogamy” and “en-dogamy” in Primitive Marriage:An Inquiry into the Origins of the Form of Capture in Marriage Ceremo-nies(1865) .In this book...  相似文献   
67.
3D printing (3DP) has been heralded as a revolutionary technology that can alter the way production is organized across time and space – with important redistributive effects on geography and size of production activities. In this article, we examine the impacts that a widespread adoption of 3DP could have on restructuring, upgrading and distributing value added along manufacturing global value chains (GVC) – with brief examples from the aerospace and automotive industries. We highlight two possible scenarios for GVCs – a complementarity scenario of 3DP and traditional manufacturing overlapping, which would reproduce power relations in GVCs and the current distribution of value added in a ‘smiling curve’; and a substitution scenario of 3DP partly or fully superseding traditional manufacturing, which would have more transformational effects in terms of ‘rebundling’ activities, regionalizing or localizing GVCs, and flattening the smiling curve into a ‘smirk’.  相似文献   
68.
For normal populations with unequal variances, we develop matching priors and reference priors for a linear combination of the means. Here, we find three second-order matching priors: a highest posterior density (HPD) matching prior, a cumulative distribution function (CDF) matching prior, and a likelihood ratio (LR) matching prior. Furthermore, we show that the reference priors are all first-order matching priors, but that they do not satisfy the second-order matching criterion that establishes the symmetry and the unimodality of the posterior under the developed priors. The results of a simulation indicate that the second-order matching prior outperforms the reference priors in terms of matching the target coverage probabilities, in a frequentist sense. Finally, we compare the Bayesian credible intervals based on the developed priors with the confidence intervals derived from real data.  相似文献   
69.
Consider a process satisfying a stochastic differential equation with unknown drift parameter, and suppose that discrete observations are given. It is known that a simple least squares estimator (LSE) can be consistent but numerically unstable in the sense of large standard deviations under finite samples when the noise process has jumps. We propose a filter to cut large shocks from data and construct the same LSE from data selected by the filter. The proposed estimator can be asymptotically equivalent to the usual LSE, whose asymptotic distribution strongly depends on the noise process. However, in numerical study, it looked asymptotically normal in an example where filter was chosen suitably, and the noise was a Lévy process. We will try to justify this phenomenon mathematically, under certain restricted assumptions.  相似文献   
70.
The heterogeneity of error variance often causes a huge interpretive problem in linear regression analysis. Before taking any remedial measures we first need to detect this problem. A large number of diagnostic plots are now available in the literature for detecting heteroscedasticity of error variances. Among them the ‘residuals’ and ‘fits’ (R–F) plot is very popular and commonly used. In the R–F plot residuals are plotted against the fitted responses, where both these components are obtained using the ordinary least squares (OLS) method. It is now evident that the OLS fits and residuals suffer a huge setback in the presence of unusual observations and hence the R–F plot may not exhibit the real scenario. The deletion residuals based on a data set free from all unusual cases should estimate the true errors in a better way than the OLS residuals. In this paper we propose ‘deletion residuals’ and the ‘deletion fits’ (DR–DF) plot for the detection of the heterogeneity of error variances in a linear regression model to get a more convincing and reliable graphical display. Examples show that this plot locates unusual observations more clearly than the R–F plot. The advantage of using deletion residuals in the detection of heteroscedasticity of error variance is investigated through Monte Carlo simulations under a variety of situations.  相似文献   
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