Improved likelihood inferences for Weibull regression model

A general procedure is developed for bias-correcting the maximum likelihood estimators (MLEs) of the parameters of Weibull regression model with either complete or right-censored data. Following the bias correction, variance corrections and hence improved t-ratios for model parameters are presented. Potentially improved t-ratios for other reliability-related quantities are also discussed. Simulation results show that the proposed method is effective in correcting the bias of the MLEs, and the resulted t-ratios generally improve over the regular t-ratios.     

Designing a multiple state repetitive group sampling plan based on the coefficient of variation

A multiple state repetitive group sampling (MSRGS) plan is developed on the basis of the coefficient of variation (CV) of the quality characteristic which follows a normal distribution with unknown mean and variance. The optimal plan parameters of the proposed plan are solved by a nonlinear optimization model, which satisfies the given producer's risk and consumer's risk at the same time and minimizes the average sample number required for inspection. The advantages of the proposed MSRGS plan over the existing sampling plans are discussed. Finally an example is given to illustrate the proposed plan.     

代内剥削与代际剥削?——基于九省百村调查的中国农村彩礼研究

中国农村地区的彩礼在过去的几十年间飞速上涨,目前已经成为农村家庭的沉重负担,高额彩礼被认为是剥削现象.本文利用2014年中国九省241个村庄的专项调查数据,使用分层回归模型,定量地分析了农村地区彩礼的代内剥削和代际剥削现象.研究结果表明,高额彩礼下家庭内兄弟之间稀释型的代内剥削是存在的,但关于兄弟对姐妹的替代型代内剥削并未得到证实;代际剥削在20世纪90年代以后结婚队列中越来越严重,结婚时即分家愈发普遍,彩礼要价也越来越高,彩礼更多地"资助"到新婚家庭.男方父母是高额彩礼代内剥削和代际剥削的最终承担者,这对于他们的生计和养老带来极大挑战.     

中国流动人口通婚圈地域结构分析

本文使用2011—2013年中国流动人口动态监测数据,利用空间分析方法对流动人口地理通婚圈的地域模式与圈层结构进行分析发现:不同区域之间的通婚地域模式具有显著的差异,东部地区的跨省通婚明显高于东北地区和西部地区,中部地区处于最低水平.地理通婚圈的空间圈层结构不但呈现出"空间等级分层"的物理结构,而且不同圈层本身的结构形态也存在显著的差异.地理通婚圈结构自内向外,出现了通婚圆→通婚弧→通婚点的梯度演化.此外,地理通婚圈分异还具有一定的方向偏好.     

被迫好评情景下消费者后续行为意愿研究

在社交网络不断兴起的环境下,越来越多的企业试图以物质奖励促使消费者进行好评以实现口碑营销,物质奖励涉及赠品、现金、价格折扣等各种形式。企业激励口碑的活动是指一家企业对“消费者对消费者”沟通的主动管理,被广泛地应用于各类面向消费者的企业,而好评返利的口碑激励模式难免被框定于回避框架下,即消费者为了避免损失而不得不在线发布正面口碑,已有关于被动口碑传播的研究主要从积极方面探讨如何利用物质奖励促进口碑传播。 在已有研究的基础上补充物质奖励对消费者口碑影响的消极方面,以心理抗拒理论和认知一致性理论为基础,以被动口碑传播为研究视角,探讨消费者在被迫实施好评之后的后续行为意愿及其影响机制。在两个行为学实验中,分别选取在职学生和普通消费者为研究样本,通过SPSS软件进行方差分析、回归分析和Bootstrap中介效应分析。 研究结果表明,①在被迫好评的情景下,抗拒体验消极影响消费者的后续行为意愿,如降低未来的口碑推荐意愿、增加删去被迫评论意愿;②产品的实际体验与口碑内容的一致性感知积极影响后续行为意愿,这一过程受到抗拒体验的中介作用;③与抗拒特质较弱的消费者相比,抗拒特质较强的消费者更倾向于产生消极的后续行为意愿;④消费者的抗拒特质调节实际体验与口碑内容的一致性感知对后续行为意愿的影响,抗拒特质较强时一致性感知对后续行为意愿的影响较低。 研究结果为企业实施激励式口碑营销提供了理论指导,丰富和发展了口碑营销和心理抗拒理论。研究结论启示企业在使用好评返利的营销策略时,应当尽可能框定于“好评则得到”而非“不好评则损失”的框架下。如果产品或服务非常依赖于消费者的重复购买行为,那么被迫好评会消极影响消费者的整体满意度并抑制后续的购买行为。商家必须认识到被迫好评的消极影响,虽然产品或服务的积极体验可以有效抑制消费者产生消极的行为反应,但是却不会对所有消费者有效,比如那些抗拒特质较强的消费者。     

光滑暧昧模型下的不透明交易和管制措施研究

本文假定透明交易者对额外投资机会回报率的标准差(方差,投资风险)存在暧昧,这种认知暧昧性抑制了透明交易者的投资行为,会导致风险资产溢价过高及社会福利损失.透明交易者是暧昧厌恶的投资者,其投资决策依据光滑暧昧厌恶模型,需求函数呈现连续且光滑的特征.而不透明交易者,通过支付一定的信息获取成本获得私有信息而具有信息优势,他们是标准的风险厌恶的投资者.通过构建理性预期均衡,本文的研究发现:初始资产严格为正的透明交易者将获得严格为正的超额收益;提高信息获取成本将减少不透明交易者的比例,从而增加风险资产溢价,降低福利水平,因而不是一项好的管制措施;而旨在提高市场透明度降低交易者暧昧性的举措总有利于提高福利水平.     

股权众筹投融资方的最优策略分析

分析了股权众筹融资方和投资方的最优策略.依据股权众筹的流程,构建了股权众筹过程中投融资方利益博弈的3阶段模型,并在同时满足融资方与投资方预期收益最大化的条件下,求解了相应的最优化问题并给出了投融资方最优策略的解析式.研究结果表明,在参数满足一定条件时,股权众筹投融资方均存在最优策略,且最优策略受边际收益、项目成功概率、预期回报率等因素的影响.     

Improved upper bound for the degenerate and star chromatic numbers of graphs

Let \(G=G(V,E)\) be a graph. A proper coloring of G is a function \(f:V\rightarrow N\) such that \(f(x)\ne f(y)\) for every edge \(xy\in E\). A proper coloring of a graph G such that for every \(k\ge 1\), the union of any k color classes induces a \((k-1)\)-degenerate subgraph is called a degenerate coloring; a proper coloring of a graph with no two-colored \(P_{4}\) is called a star coloring. If a coloring is both degenerate and star, then we call it a degenerate star coloring of graph. The corresponding chromatic number is denoted as \(\chi _{sd}(G)\). In this paper, we employ entropy compression method to obtain a new upper bound \(\chi _{sd}(G)\le \lceil \frac{19}{6}\Delta ^{\frac{3}{2}}+5\Delta \rceil \) for general graph G.     

The thickness of the complete multipartite graphs and the join of graphs

The thickness of a graph is the minimum number of planar spanning subgraphs into which the graph can be decomposed. It is known for relatively few classes of graphs, compared to other topological invariants, e.g., genus and crossing number. For the complete bipartite graphs, Beineke et al. (Proc Camb Philos Soc 60:1–5, 1964) gave the answer for most graphs in this family in 1964. In this paper, we derive formulas and bounds for the thickness of some complete k-partite graphs. And some properties for the thickness for the join of two graphs are also obtained.     

Reconfigured Reciprocity: How Aging Taiwanese Immigrants Transform Cultural Logics of Elder Care

Drawing on 55 interviews with older Taiwanese immigrants who relocated to the United States at an earlier life stage, the author argues that changing contextual features involved in the processes of international migration encourage and even demand aging immigrants to reconstruct cultural logics of aging and geriatric care. He develops the concept of reconfigured reciprocity to demonstrate how aging migrant populations transform cultural logics of intergenerational responsibility, obligation, and entitlement to reconcile the tension between ethnic tradition and modernity. First, he reveals how many of the respondents' lack of caregiving for their own parents undermines their sense of entitlement to receive care from younger generations. Furthermore, he highlights how the structural squeeze among work, family, and caregiving with which the younger generation struggles further discourages the respondents from relying on their children. Finally, the author underscores how aging immigrants evoke the concept of Americanization to reconstruct expectations of how they should be taken care of in their twilight years.