梁启超笔下的谭嗣同——关于《仁学》的刊行与梁撰《谭嗣同传》

谭嗣同被捕就义之前,曾向梁启超表示彼此要像日本明治维新志士月照与西乡那样,分别承担死者与生者的责任。亡命日本以后,梁启超很快将谭嗣同遗稿《仁学》发表在《清议极》上,履行自己作为生者的责任。然而《仁学》的发表颇经周折,多次中断,且有删改,刊载历时3年。与此同时,梁启超写过3篇《谭嗣同传》,其中的内容各有不同。这些不正常的情况,耐人寻味,反映了清末社会历史大变动时期梁启超思想演变的明确轨迹,以及梁启超思想的复杂性和"多变"中的诚实性。     

对我国社会养老保险的再思考——智利模式的启示

我国现行社会统筹与个人账户相结合的基本养老保险制度,为城镇老年职工的基本生活提供了一定保障。但现行养老保险制度是一个效率缺失的制度安排。为解决这一问题,有必要借鉴智利养老保险制度改革的成功经验,通过政府承担转轨成本、实行完全积累的强制性个人账户制、基金运营引入市场化竞争机制等措施,健全和完善我国的社会养老保障制度。     

供应链中考虑零售商损失规避的交易契约研究

一个零售商和一个供应商组成的供应链系统,零售商以一定的概率具备损失规避特性,供应商根据此概率大小设计交易契约最大化自身利润。首先,采用博弈和激励机制理论,分别研究了混同契约和甄别契约的设计过程。在混同契约下,供应商针对不同类型的零售商制定统一批发价格,零售商根据该批发价格决定其最优订货量;在甄别契约下,供应商通过设计契约菜单激励零售商显示其真实的损失规避特性。得出,当产品生产成本较低时,供应商可以设计出有效的甄别契约,通过比较混同与甄别契约下的供应商最优期望利润得到最优契约;而当产品成本较高时,不存在有效的甄别契约,此时混同契约即为最优契约。其次,通过数值模拟,对比了在产品生产成本较低时的两种契约下,零售商具有损失规避特征的概率及其损失规避程度对供应商期望利润及零售商期望效用、期望利润的影响;得出,当存在有效的甄别契约时,供应商采用甄别契约总比采用混同契约所得的期望利润更高。     

需求-汇率风险聚集下的汇率风险对冲与批发价激励

以一个由上游制造商和下游零售商组成的二级供应链为建模背景,在汇率风险和需求风险聚集(pooling)在下游零售商的情况下,分别建立了有无批发价激励情形下的两个动态博弈模型,获得了相应的均衡。通过分析相应的均衡,结果表明,(1)在两种情形下,零售商的汇率风险对冲行为具有稳定供应链生产行为的作用,但批发价激励能够提高零售商的汇率风险对冲比例和供应链节点企业间的交易价格;(2)与无批发价激励的情形相比,有批发价激励时的制造商利润较高,从而制造商有使用批发价激励零售商对冲汇率风险的动机;(3)在风险聚集下,"通过较低的批发价来激励零售商对冲汇率风险"这一策略能够实现供应链盈利水平与风险承担之间的权衡:需求和汇率风险增加均会使得供应链节点企业和供应链整体的盈利水平降低,同时也将降低风险聚集处的节点企业和供应链整体的利润方差。     

民意调查中真实性“公共民意”获取的方法论路径

通过民意调查,真实地反映民众对公共事务的社会态度和公共民意;使前者成为社会变迁预警系统的构建基础,后者成为引导与确证公共政策问题形成的起点。既往的民意调查方法,由于简单地移植了一般社会调查方法的技术工具,无法克服伪装型社会态度和虚假型公共民意的出现。通过定期统计网络特定多数议题的修辞框架,把握真实性民意的社会态度;通过行政吸纳政治的制度培育路径,发掘和引领公共民意的价值生成;是完善和创新当代中国民意调查方法的重要路径。     

Nonparametric-likelihood inference based on cost-effectively-sampled-data

Costs associated with the evaluation of biomarkers can restrict the number of relevant biological samples to be measured. This common problem has been dealt with extensively in the epidemiologic and biostatistical literature that proposes to apply different cost-efficient procedures, including pooling and random sampling strategies. The pooling design has been widely addressed as a very efficient sampling method under certain parametric assumptions regarding data distribution. When cost is not a main factor in the evaluation of biomarkers but measurement is subject to a limit of detection, a common instrument limitation on the measurement process, the pooling design can partially overcome this instrumental limitation. In certain situations, the pooling design can provide data that is less informative than a simple random sample; however this is not always the case. Pooled-data-based nonparametric inferences have not been well addressed in the literature. In this article, a distribution-free method based on the empirical likelihood technique is proposed to substitute the traditional parametric-likelihood approach, providing the true coverage, confidence interval estimation and powerful tests based on data obtained after the cost-efficient designs. We also consider several nonparametric tests to compare with the proposed procedure. We examine the proposed methodology via a broad Monte Carlo study and a real data example.     

Bridging: Locating critical connectors in a network

This paper proposes several measures for bridging in networks derived from Granovetter's (1973) insight that links which reduce distances in a network are important structural bridges. Bridging is calculated by systematically deleting links and calculating the resultant changes in network cohesion (measured as the inverse average path length). The average change for each node's links provides an individual level measure of bridging. We also present a normalized version which controls for network size and a network-level bridging index. Bridging properties are demonstrated on hypothetical networks, empirical networks, and a set of 100 randomly generated networks to show how the bridging measure correlates with existing network measures such as degree, personal network density, constraint, closeness centrality, betweenness centrality, and vitality. Bridging and the accompanying methodology provide a family of new network measures useful for studying network structure, network dynamics, and network effects on substantive behavioral phenomenon.     

Risk Finance for Catastrophe Losses with Pareto‐Calibrated Lévy‐Stable Severities

For catastrophe losses, the conventional risk finance paradigm of enterprise risk management identifies transfer, as opposed to pooling or avoidance, as the preferred solution. However, this analysis does not necessarily account for differences between light‐ and heavy‐tailed characteristics of loss portfolios. Of particular concern are the decreasing benefits of diversification (through pooling) as the tails of severity distributions become heavier. In the present article, we study a loss portfolio characterized by nonstochastic frequency and a class of Lévy‐stable severity distributions calibrated to match the parameters of the Pareto II distribution. We then propose a conservative risk finance paradigm that can be used to prepare the firm for worst‐case scenarios with regard to both (1) the firm's intrinsic sensitivity to risk and (2) the heaviness of the severity's tail.     

Moral opinion polarization and the erosion of trust

Since Puntam's seminal work on declining levels of social capital, the question of how social trust is formed has reached unprecedented heights of critical enquiry. While most of the current research concentrates on ethnic diversity and income inequality as the main influences driving down generalized trust, we focus on opinion polarization as another potential impact factor on trust. In more detail, we investigate the extent to which polarization over morally charged issues such as homsexuality, abortion and euthanasia affects individuals' likelihood to trust others. We hypothesize that moral issues have a natural tendency to divide societies' opinions into opposing poles and, thus, to challenge social cohesion in modern civil societies. Based on hierarchical analyses of the fifth wave of the World Values Survey (WVS) — comprising a sample of 39 countries — our results reveal that individuals living in countries characterized by more opinion polarization tend to have less trust in other people.     

Bayesian Poisson models for the graphical combination of dependent expert information

A supra-Bayesian (SB) wants to combine the information from a group of k experts to produce her distribution of a probability θ. Each expert gives his counts of what he thinks are the numbers of successes and failures in a sequence of independent trials, each with probability θ of success. These counts, used as a surrogate for each expert's own individual probability assessment (together with his associated level of confidence in his estimate), allow the SB to build various plausible conjugate models. Such models reflect her beliefs about the reliability of different experts and take account of different possible patterns of overlap of information between them. Corresponding combination rules are then obtained and compared with other more established rules and their properties examined.