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61.
为了更有效的规避影响保险市场交易效率的逆向选择问题,本文分投保人风险类型为两种和多种情形建立了带奖惩金的两期保险契约模型,首次提出可以用奖励金和惩罚金有效甄别投保人的风险类型。该模型根据投保人第一个保险期内的索赔情况在第二个保险期对其进行奖励或惩罚,高风险类型的投保人如果选择为低风险类型投保人设计的保险契约,则其在第二阶段受到惩罚的概率要远远大于得到奖励的概率,即风险越高的投保人越害怕惩罚金,因此所建模型满足斯彭斯-莫里斯分离条件。带奖惩金的两期保险契约模型中保险公司的期望利润仍然为0,并不会给投保人带来额外的经济负担,却能够实现对传统部分保险契约简单重复两次的严格帕累托改进。最后采用一个算例说明了该模型的有效性。  相似文献   
62.
Abstract

Purpose: This paper presents a combined multi-phase supplier selection model. The process repeatedly revisits the criteria and sourcing decision as the development process continues. This enables a structured adoption of product and production system innovation from strategic suppliers, where previously the literature purely focuses on product innovation or cost reduction. Design/methodology/approach: The authors adopted an embedded researcher style, inductive, qualitative case study of an industrial supply cluster comprising a focal automotive company and its interaction with three different strategic stamping suppliers. Findings: Our contribution is the multi-phased production and product innovation process. This is an advance from traditional supplier selection and also an extension of ideas of supplier-located product development as it includes production system development, and complements the literature on working with strategic suppliers. Specifically, we explicitly articulate the previously unreported issue of whether a supplier chosen for its innovation capabilities at the start of the new product development process will also be the most appropriate supplier during the production system development phase, when an ability to work collaboratively may be the most important attribute, or in the large-scale production phase when an ability to manufacture at low unit cost may be most important. Originality/value: The paper identifies a multi-phase approach to tendering within a fixed body of strategic suppliers which seeks to identify the optimum technological and process decisions as well as the traditional supplier sourcing choice. These areas have not been combined before and generate a valuable approach for firms to adopt as well as for researchers to extend our understanding of a highly complex process.  相似文献   
63.
This article examines the limitations of using a single advocacy-accommodation continuum when depicting organizational stance and movement in conflict situations (Cancel et al., 1997). The authors argue that advocacy and accommodation can vary independently in response to a variety of contingent factors. To comprehensively capture the locations and motions that are possible in organization-public conflicts, a two-continuum approach is proposed. Separate assessment of the effects of contingency variables on advocacy and accommodation can be used to accurately locate organizational stance along advocacy and accommodation continua. Strategic alternatives that cannot be depicted using a single continuum (such as favorable alignment of organization advocacy/public accommodation or unilateral change on the part of one party) can be captured if separate continua are employed. By depicting initial stances and desired directions of movement for both the organization and public, the dual-continuum approach can also provide practical guidance to public relations professionals in selecting strategies for achieving preferred outcomes and evaluating their effectiveness.  相似文献   
64.
Focusing on the model selection problems in the family of Poisson mixture models (including the Poisson mixture regression model with random effects and zero‐inflated Poisson regression model with random effects), the current paper derives two conditional Akaike information criteria. The criteria are the unbiased estimators of the conditional Akaike information based on the conditional log‐likelihood and the conditional Akaike information based on the joint log‐likelihood, respectively. The derivation is free from the specific parametric assumptions about the conditional mean of the true data‐generating model and applies to different types of estimation methods. Additionally, the derivation is not based on the asymptotic argument. Simulations show that the proposed criteria have promising estimation accuracy. In addition, it is found that the criterion based on the conditional log‐likelihood demonstrates good model selection performance under different scenarios. Two sets of real data are used to illustrate the proposed method.  相似文献   
65.
Sparsity-inducing penalties are useful tools for variable selection and are also effective for regression problems where the data are functions. We consider the problem of selecting not only variables but also decision boundaries in multiclass logistic regression models for functional data, using sparse regularization. The parameters of the functional logistic regression model are estimated in the framework of the penalized likelihood method with the sparse group lasso-type penalty, and then tuning parameters for the model are selected using the model selection criterion. The effectiveness of the proposed method is investigated through simulation studies and the analysis of a gene expression data set.  相似文献   
66.
In Wu and Zen (1999), a linear model selection procedure based on M-estimation is proposed, which includes many classical model selection criteria as its special cases, and it is shown that the selection procedure is strongly consistent for a variety of penalty functions. In this paper, we will investigate its small sample performances for some choices of fixed penalty functions. It can be seen that the performance varies with the choice of the penalty. Hence, a randomized penalty based on observed data is proposed, which preserves the consistency property and provides improved performance over a fixed choice of penalty functions.  相似文献   
67.
量刑程序与定罪程序一样是刑事审判环节,具有独立性与依附性特征,而我国立法层面的量刑程序几乎是空白。我国在现有的司法环境下实行相对独立的量刑程序符合国际司法潮流,这一程序也没有增加各诉讼参加人的负担,较易操作落实,且有相关的配套程序和实践基础,因此具有可行性。但在实践中应注意一些问题,如要清晰控辩审三方在量刑程序中的定位,使社会调查报告机制走向制度化、专业化,判决书中应对量刑的依据和理由进行阐述等。  相似文献   
68.
A test statistic proposed by Li (1999) for testing the adequacy of heteroscedastic nonlinear regression models using nonparametric kernel smoothers is applied to testing for linearity in generalized linear models. Simulation results for models with centered gamma and inverse Gaussian errors are presented to illustrate the performance of the resulting test compared with log-likelihood ratio tests for specific parametric alternatives. The test is applied to a data set of coronary heart disease status (Hosmer and Lemeshow, (1990).  相似文献   
69.
对2005年至2014年间刊登于五本杂志上的365则女性征婚启事进行内容分析和统计检验,发现在女性征婚者的自我陈述和择偶要求中,既有较为稳定的传统标准,也存在一些时代变化。女性自身的职业和文化程度提及率较高,择偶标准中道德品质和个性、个人素质等受到了更多关注。在社会资源方面,隐性的资源更被强调,择偶标准呈现多元化取向。在更年轻和文化程度更高的女性中,体现出了更具现代性的择偶标准。有婚史和有孩子的女性则更多地关注一些现实性的标准。  相似文献   
70.
We propose a new procedure for the multinomial selection problem to solve a real problem of any modern Air Force: the elaboration of better air-to-air tactics for Beyond Visual Range air-to-air combat that maximize its aircraft survival probability H(θ, ω), as well as enemy aircraft downing probability G(θ, ω). In this study, using a low-resolution simulator with generic parameters for the aircraft and missiles, we could increase an average success rate of 16.69% and 16.23% for H(θ, ω) and G(θ, ω), respectively, to an average success rate of 76.85% and 79.30%. We can assure with low probability of being wrong that the selected tactic has greater probability of yielding greater success rates in both H(θ, ω) and G(θ, ω) than any simulated tactic.  相似文献   
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