回归诊断在统计数据异常值探测中的应用

近年来有关异常值的理论探讨一直是个热点问题，从回归模型诊断的角度对统计数据中的异常值进行探测与分析，并在基于R语言的基础上，结合具体实例，给出回归诊断在统计数据异常值探测中的应用。     

Cost-effectiveness modeling for neuropathic pain treatments: investigating the relative importance of parameters using an open-source model

Aims: The study objective was to develop an open-source replicate of a cost-effectiveness model developed by National Institute for Health and Care (NICE), in order to explore uncertainties in health economic modeling of novel pharmacological neuropathic pain treatments.

Materials and methods: The NICE model, consisting of a decision tree with branches for discrete levels of pain relief and adverse event (AE) severities, was replicated using R, and used to compare a hypothetical neuropathic pain drug to pregabalin. Model parameters were sourced from NICE’s clinical guidelines and associated with probability distributions to account for underlying uncertainty. A simulation-based scenario analysis was conducted to assess how uncertainty in efficacy and AEs affected the net monetary benefit (NMB) for the hypothetical treatment at a cost-effectiveness threshold of £20,000 per QALY.

Results: Relative to pregabalin, an increase in efficacy was associated with greater NMB than an improvement in tolerability. A greater NMB was observed when efficacy was marginally higher than that of pregabalin, while maintaining the same level of AEs than when efficacy was equivalent to pregabalin, but with a more substantial reduction in AEs. In the latter scenario, the NMB was only positive at a low cost-effectiveness threshold.

Limitations: The replicate model shares the limitations described in the NICE guidelines. There is a lack of support in scientific literature for the assumption that increased efficacy is associated with a greater reduction in tolerability. The replicate model also included a single comparator, unlike the NICE model.

Conclusions: Pain relief is a stronger driver of NMB than tolerability, at a cost-effectiveness threshold of £20,000 per QALY. Health technology assessment decisions which are influenced by NICE’s model may reward efficacy gains, even if they are associated with more severe AEs. This contrasts with recommendations from clinical guidelines for neuropathic pain, which place more equal weighting on improvements in efficacy and tolerability as value drivers.     

中国在“一带一路”区域的投资结构变化及发展趋势

"一带一路"区域在中国对外投资中的地位日益重要,投资收益能否得到保障至关重要。以中国在"一带一路"区域投资结构为研究对象,从数量、地区、行业等方面分析投资结构现状,根据投资导向差异,可以分为技术寻求型、能源导向型、效率导向型和市场需求型等四类投资。针对2011—2017年四类投资在中国对"一带一路"区域投资结构中的权重变化,选用熵值法、描述性统计和散点图相结合的分析方法辅助研究,结果显示:第一,受中国能源安全战略和供给侧结构性改革的影响,能源导向型投资和市场需求型投资的权重不断加大,但中国在"一带一路"区域的投资结构未发生根本性变化;第二,技术寻求型投资因沿线国家普遍缺乏先进技术、知识产权保护意识和研究成果转化能力而面临低品质发展的危险;第三,随着互联互通进程的加速,中国的能源导向型投资呈现分散化态势,这有助于中国更好地落实能源安全战略;第四,技术导向型和市场需求型投资有高质量发展的条件和趋势,其中,技术寻求型投资以技术和成本优势为标准正在形成"两升一降"的投资格局,但是有助于中国提升国际竞争力的高效率投资比重小,市场需求型投资以一般贸易和产业链形式可以促使中国与沿线国家经济结构的互补性得到充分发挥,切实在"一带一路"区域形成共享经济体。     

Tax(i)ing the Poor? Commuting Costs in South African Cities

In this paper, I describe the monetary and time costs of commuting to work in South African cities, and how these have changed in the post‐Apartheid era. I interpret these results in light of a paper by Brueckner, who used a simple urban model to suggest that location and commuting patterns by race could change as a result of the repeal of Apartheid era legislation such as the Group Areas Act that made it impossible for black South Africans to live near the centre of cities. A key finding is that monetary and time costs of commuting in South African cities are high and have increased in the post‐Apartheid period. Journey times are much higher than the OECD country average and a sample of developing country cities. Part of the explanation for increasing average commute times is population growth in South African cities, which has been substantial. Both the population and number of commuters doubled between 1993 and 2013 in the six metropolitan municipalities (metros) analysed in this paper. Since commuting costs a substantial amount and generates negative externalities through congestion I also explore the financing of public transport.     

银行3R营销策略-花旗银行在日本的案例分析

“3R”策略是银行营销的核心内容。能否在市场经营战略中对此进行有效的应用，是决定一个银行能否在竞争中获胜的重要因素。在金融业竞争日趋激烈以及竞争范围日趋全球化的今天，“3R”策略的应用显得尤为重要．这一点从花旗银行在日本的营销案例中得到了充分的证明。     

R与当前大数据审计方法的比较研究

当前,审计人员进行数据分析时以Excel统计计算、SQL语句查询分析为主,而在大数据时代来临之际,这两种工具是否仍能继续作为大数据审计工具协助开展审计工作,本文将结合R语言,分别对其展开比较研究,为将来审计人员开展大数据审计提供基础的理论参考。     

交叉验证在数据建模模型选择中的应用

交叉验证（CrossValidation）在模型选择中具有重要作用。在基于R语言的条件下,结合具体实例,LOO-CV交叉验证方法拟合的结果和模型拟合的图形是高度吻合的,结果的区分度也比较大;R程序算法在编制LOO-CV交叉验证方法程序比较简单,可以根据具体情况修改程序,具有明显的优势。