Reflections on discriminant validity: Reexamining the Bove et al. (2009) findings

Bove, Pervan, Beatty and Shiu (2009) develop and test a latent variable model of the role of service workers in encouraging helpful behaviors by customers towards the service business (OCBs). Farrell (2010) questions these findings due to an incorrect application of the Fornell and Larcker (1981) discriminant validity test. The authors respond to Farrell's criticism by discussing the options available for assessing discriminant validity, the current use of these options in top journals, the underlying assumptions of these assessments, and the appropriateness of the alternative assessments under different types of situations. Finally, the authors address the specific concerns raised in Farrell (2010) in regard to Bove et al. (2009).     

在数学建模中培养学生创新性思维及建议

本文论述了数学建模对培养学生创新能力、提高综合素质的重要作用,指出大学生创新性思维能力的培养是数学建模活动的核心目标,对在数学建模活动中如何培养学生的创新性思维能力作了讨论,并根据学校开设数学建模课程及参加数学建模竞赛活动的现状,就如何提高数学建模成绩提出了一些建议.     

When do B2B brands influence the decision making of organizational buyers? An examination of the relationship between purchase risk and brand sensitivity

The dominant perspective on organizational buying behavior suggests that buyers tend to rely on objective criteria when making product choice decisions and that the potential influence of subjective cues, such as brands, on buyer decision making decreases with increasing risk. An alternative perspective, confirmed in this study by in-depth interviews with various managers, suggests that brands serve as a risk-reduction heuristic, whereby the influence of brands on decision making increases as a function of risk. Building on risk and information processing theories, this research builds on these complementary perspectives to propose that risk and brand sensitivity relate in a U-shaped manner, where brand sensitivity is highest in relatively low- or high-risk situations. The results of scenario- and survey-based field studies—involving 206 and 180 members of buying centers, respectively—suggest that both perspectives have merit and support the proposed nonlinear relationship. Moreover, the findings reveal that the risk-brand sensitivity relationship is moderated by competitive intensity, such that the linear (negative) and quadratic (positive) effects are stronger when competitive intensity is low.     

Accommodating spatial correlation across choice alternatives in discrete choice models: an application to modeling residential location choice behavior

This paper presents a modeling methodology capable of accounting for spatial correlation across choice alternatives in discrete choice modeling applications. Many location choice (e.g., residential location, workplace location, destination location) modeling contexts involve choice sets where alternatives are spatially correlated with one another due to unobserved factors. In the presence of such spatial correlation, traditional discrete choice modeling methods that are often based on the assumption of independence among choice alternatives are not appropriate. In this paper, a Generalized Spatially Correlated Logit (GSCL) model that allows one to represent the degree of spatial correlation as a function of a multi-dimensional vector of attributes characterizing each pair of location choice alternatives is formulated and presented. The formulation of the GSCL model allows one to accommodate alternative correlation mechanisms rather than pre-imposing restrictive correlation assumptions on the location choice alternatives. The model is applied to the analysis of residential location choice behavior using a sample of households drawn from the 2000 San Francisco Bay Area Travel Survey (BATS) data set. Model estimation results obtained from the GSCL are compared against those obtained using the standard multinomial logit (MNL) model and the spatially correlated logit (SCL) model where only correlations across neighboring (or adjacent) alternatives are accommodated. Model findings suggest that there is significant spatial correlation across alternatives that do not share a common boundary, and that the GSCL offers the ability to more accurately capture spatial location choice behavior.     

浅谈培养和提高学生数学建模能力的对策

数学建模是一种数学思想方法,可以帮助学生灵活地综合地应用所学的知识来处理和解决一些现实生活中的问题.文章首先对数学建模的步骤、数学建模能力作了介绍;接着分析学生在数学建模中存在的问题,并针对问题提出培养和提高学生数学建模能力的对策.     

基于QualNet的战术数据链三维动态仿真

基于QualNet仿真软 件设计并实现了战术数据链在模拟环境下的三维动态仿真。将战术数据链仿真拓展到三维空 间,加入目标的机动性因素,给出了三维仿真的动态模型及其满足的更普遍关系式,具有一 定的参考价值和指导意义。     

技术模仿、技术创新的战略选择模型和经济增长

一国技术水平程度的高低在很大程度上影响和决定了该国经济发展的水平和经济增长的速度,技术水平提高的途径主要有两种:技术模仿和技术创新.但技术创新并不只是发达国家的"专利",技术创新除了与人均资本存量和人均人力资本水平有关外,也与总体的人均资本存量和人力资本水平有关.本文将国家技术发展战略分为四类,并给出了各种不同技术发展战略的情景条件.     

Incorporating textual information in customer churn prediction models based on a convolutional neural network

This study investigates the value added by incorporating textual data into customer churn prediction (CCP) models. It extends the previous literature by benchmarking convolutional neural networks (CNNs) against current best practices for analyzing textual data in CCP, and, using real life data from a European financial services provider, validates a framework that explains how textual data can be incorporated in a predictive model. First, the results confirm previous research showing that the inclusion of textual data in a CCP model improves its predictive performance. Second, CNNs outperform current best practices for text mining in CCP. Third, textual data are an important source of data for CCP, but unstructured textual data alone cannot create churn prediction models that are competitive with models that use traditional structured data. A calculation of the additional profit obtained from a customer retention campaign through the inclusion of textual information can be used by practitioners directly to help them make more informed decisions on whether to invest in text mining.     

基于解释结构模型的茶叶品牌发展策略——以陕西汉中茶产业为例

以解释结构模型为工具,结合具体案例,总结了影响茶叶品牌发展的因素,如企业经营模式、市场信息、企业广告促销、政府的宣传引导、目标市场和市场定位、旅游资源开发、茶叶品质、地区性标准、茶叶物流体系、农业种植规范性、茶叶加工技术、良种推广等。分析了其相互影响关系,建立茶叶品牌发展的解释结构模型。并以此为基础,探索了改变茶叶企业的经营模式、健全现代物流体系、建立有效的市场信息平台和信息系统、建立地区性标准、建设政府平台等茶叶品牌发展的策略性问题。     

Ranking Crop Yield Models: A Comment

This comment discusses key specification issues that may have affected the performance and, therefore, the ranking of parametric models that were compared in a recent AJAE article. A procedure to obtain the most flexible parametric model specification possible, given the particular probability distribution function on which the model is based is presented. These specifications also allow for standardized and, therefore, more valid comparisons across parametric models that are based on different probability distributions. Finally, the comment cautions against generalization of the rankings in that AJAE article and recommends that these more flexible specifications be adopted in future comparisons and applications.