面向网络营销企业的营销信号选择博弈分析

如何通过营销信号来降低电子市场逆向选择风险是影响网络营销企业业绩的重要因素.本文以两家企业垄断市场为例,建立了企业信号传递博弈模型.通过对分离均衡与混同均衡存在条件的分析,讨论了信号传递成本以及不同消费者群体所占比例对企业营销信号决策的影响.分析结果有助于网络营销企业在电子市场中选择营销信号.     

动态车辆路径问题排队模型分析

分析了一类动态车辆路径问题,其中顾客需求以泊松流形式出现,现场服务时间服从一般分布.提出解决该问题的两种策略:顺序服务策略和中点改进策略,利用排队论、几何概率论等领域的知识分别求出了这两种策略的系统时间,并通过仿真数据实验验证了这两种策略的有效性.     

带有快速反应策略供应链系统的补偿策略研究

过长的订购提前期往往使得零售商订货决策感到困难. 快速反应策略能使零售商在获 得更多更准确的市场需求信息后,调整订购量而提高收益. 但是快速反应策略并不一定使供应 商的利润也提高. 有文章指出只有低的服务水平才能使两者利润同时提高,因而这种方法在工 业应用中是不一定可行的. 补偿策略是一种广泛应用的方法,能够提高产品的客户服务水平, 因而研究了补偿策略在快速反应供应链系统中的作用. 在某些条件下,在快速反应供应链系统 中,补偿策略能使零售商与供应商一方的收益不变或者提高,另一方的收益有所提高,即Pare2 to 提高. 还研究了引进补偿策略后,供应链系统的最优解及期望卖出量、期望缺货量和期望残 余量的变化情况.     

教育政策的利益分析——以择校问题为例

利益是公共政策分析的基本范畴,实现公共利益是教育政策制定最重要的目标。教育政策的利益分析包括利益主体分析、利益需求分析、利益实现方式分析以及利益结果分析四个方面。从利益分析的角度来看,择校问题实际上是由于优质教育资源供需矛盾而导致的,其中教育资源分配不均衡是根本原因。择校代表了一种个人的基本权利,体现的是个人利益。通过改革不合理的教育供给方式、增加教育服务供给,是治理择校问题、平衡公共利益和私人利益的有效途径。     

基于累积前景理论的多资产投资组合优化与实证研究

基于CPT视角的多风险资产投资组合模型,探讨投资者面对不同投资风险时的心理变化以及心理变化对其投资策略的影响。通过选取不同超额收益率及波动率水平的股票,测试投资策略对于风险态度指标的敏感度。研究表明,投资者面对不同风险具有明显地心理变化,并且其心理变化对投资策略具有显著的影响。具体表现在几个方面：投资者面对不确定收益时,表现出风险厌恶,面对不确定损失时,表现出风险偏好;投资者将无风险资产的投资收益作为心理参考点,所做的投资决策与相对于此参考点的相对财富水平的变化有关,而不是与传统理论中的绝对财富变化量相关。     

企业用户云服务技术选择行为

如何选择最佳云服务方案,是企业决定采纳云服务之后所面临的一个重要决策。为了解决云服务技术选择问题,从业务流程的视角出发,以模块化系统理论为基础,提出一个流程模块化、IT可拆解性及安全风险如何影响云服务技术选择的研究模型。采用问卷调查和计量经济学的普通最小二乘法OLS进行实证分析。研究结果表明:流程模块化和IT可拆解性对云服务技术选择的抽象程度有显著的正向影响,即流程模块化程度IT可拆解性越高的企业,越倾向于选择抽象程度高的云服务,如软件即服务SaaS;而流程模块化程度和IT可拆解性越低的企业,越倾向于选择抽象程度低的云服务,如基础设施即服务IaaS。同时,安全风险会正向调节流程模块化和IT可拆解性对云服务技术选择的抽象程度的影响。     

Problem‐ and solution‐focused characteristics of parenting support, 3 years after implementation of the solution‐focused approach: A qualitative content analysis

In recent years, solution‐focused parenting support has been developed and implemented as a promising brief and strength‐based approach. Given the fundamental differences between solution‐focused and the historically more common problem‐focused parenting support and the complexity of transforming professional practice, an actual shift towards solution‐focused parenting support can be expected to be limited up to now. However, because research into the specific communication characteristics of professional parenting support is currently lacking, no conclusion can be drawn at present. Therefore, this study aims to explore the current problem‐ and solution‐focused characteristics of parenting support in the Dutch youth healthcare (YH). In total, 15 support sessions performed by 10 public health nurses were audio recorded and transcribed verbatim. A detailed qualitative content analysis of professional communication was conducted to identify problem‐ and solution‐focused factual, expressive, relational and appealing aspects of parenting support. Problem‐focused characteristics dominated all sessions of parenting support. This study is the first to thoroughly analyse the problem‐focused and solution‐focused communication characteristics of professional parenting support using a qualitative content analysis. Parenting support practice in the Dutch YH did not shift substantially to a solution‐focused approach. More effort is required to stimulate and facilitate this professional transformation.     

高新技术创新的文化路径及政策选择

相对一般的技术创新，高新技术创新有其独有的一些特点，这些特点决定了文化对高新技术创新具有重要作用。高新技术创新的文化路径包括观念文化路径、制度文化路径和行动文化路径三个方面。基于文化视角优化高新技术创新的政策选择，完善我国科技政策，有助于推动高新技术的进一步创新。     

A likelihood ratio test to discriminate exponential–Poisson and gamma distributions

The exponential–Poisson (EP) distribution with scale and shape parameters β>0 and λ∈?, respectively, is a lifetime distribution obtained by mixing exponential and zero-truncated Poisson models. The EP distribution has been a good alternative to the gamma distribution for modelling lifetime, reliability and time intervals of successive natural disasters. Both EP and gamma distributions have some similarities and properties in common, for example, their densities may be strictly decreasing or unimodal, and their hazard rate functions may be decreasing, increasing or constant depending on their shape parameters. On the other hand, the EP distribution has several interesting applications based on stochastic representations involving maximum and minimum of iid exponential variables (with random sample size) which make it of distinguishable scientific importance from the gamma distribution. Given the similarities and different scientific relevance between these models, one question of interest is how to discriminate them. With this in mind, we propose a likelihood ratio test based on Cox's statistic to discriminate the EP and gamma distributions. The asymptotic distribution of the normalized logarithm of the ratio of the maximized likelihoods under two null hypotheses – data come from EP or gamma distributions – is provided. With this, we obtain the probabilities of correct selection. Hence, we propose to choose the model that maximizes the probability of correct selection (PCS). We also determinate the minimum sample size required to discriminate the EP and gamma distributions when the PCS and a given tolerance level based on some distance are before stated. A simulation study to evaluate the accuracy of the asymptotic probabilities of correct selection is also presented. The paper is motivated by two applications to real data sets.     

An access network design problem with end-to-end QoS constraints

In this paper, we present an access network design problem with end-to-end quality of service (QoS) requirement. The problem can be conceptualized as a two-level hierarchical location-allocation problem on the tree topology with nonlinear side constraints. The objective function of the nonlinear mixed integer programming model minimizes the total cost of switch and fiber cable, while satisfying demand within the prescribed level of QoS. By exploiting the inherent structure of the nonlinear QoS constraints, we develop linearization techniques for finding an optimal solution. Also, we devise an effective exact optimal algorithm within the context of disjunctive constraint generation. We present promising computational results that demonstrate the effectiveness of the proposed solution procedure.