Inventory‐Based Dynamic Pricing with Costly Price Adjustment

We study an average‐cost stochastic inventory control problem in which the firm can replenish inventory and adjust the price at anytime. We establish the optimality to change the price from low to high in each replenishment cycle as inventory is depleted. With costly price adjustment, scale economies of inventory replenishment are reflected in the cycle time instead of lot size—An increased fixed ordering cost leads to an extended replenishment cycle but does not necessarily increase the order quantity. A reduced marginal cost of ordering calls for an increased order quantity, as well as speeding up product selling within a cycle. We derive useful properties of the profit function that allows for reducing computational complexity of the problem. For systems requiring short replenishment cycles, the optimal solution can be easily computed by applying these properties. For systems requiring long replenishment cycles, we further consider a relaxed problem that is computational tractable. Under this relaxation, the sum of fixed ordering cost and price adjustment cost is equal to (greater than, less than) the total inventory holding cost within a replenishment cycle when the inventory holding cost is linear (convex, concave) in the stock level. Moreover, under the optimal solution, the time‐average profit is the same across all price segments when the inventory holding cost is accounted properly. Through a numerical study, we demonstrate that inventory‐based dynamic pricing can lead to significant profit improvement compared with static pricing and limited price adjustment can yield a benefit that is close to unlimited price adjustment. To be able to enjoy the benefit of dynamic pricing, however, it is important to appropriately choose inventory levels at which the price is revised.     

中国粮食增产的主要因素贡献分解与实证估算

已有测算中国粮食增产要素贡献率的方法存在虚增或低估某要素贡献率的缺陷,文章通过改进粮食增产贡献率测算方法实证估计了2003—2016年期间单产、播种面积和结构调整对中国粮食增产的贡献。结果表明,中国粮食实现“十二连增”的巨大成就主要是单产增长贡献,年均贡献率50%以上,播种面积和作物内部结构调整也是不可忽视的重要力量,年均贡献率分别为30%与10%以上。然而,未来中国粮食增产依靠播种面积扩大和结构调整的空间变窄,需要探索新的增产路径。     

如何解释资本结构的调整方式和速度--基于福耀玻璃的案例分析与讨论

以现有资本结构理论为基础,试图寻找能解释各种典型公司资本结构调整方式和速度的理论框架。首先以案例分析为基础分析了主流资本结构理论对案例公司资本结构调整方式的解释程度和解释异同。然后结合公司的财务政策,定性分析了主流理论对于资本结构调整方式存在解释异同的背后原因以及将主流理论融合的理论框架。认为从资金供需的角度理解权衡理论和优序融资理论以及市场择时理论,可以将这些主流理论统一起来解释各种典型的资本结构调整方式。同时,发现以计量模型估算的资本结构调整速度推断资本结构调整到目标水平所需的时间,会误导人们对于资本结构调整方式的理解。     

陈大为:新生代意识的诠释者

陈大为以教学、研究、创作"三栖"的状态表明着他作为新生代意识的阐释者的地位,他往往以"先发制人"的理论、挑战的姿态去揭示抑制在现行文学秩序深层的盲视,又"后发制人"地以自身的创作实践拓展颠覆既存意识形态的潜能。他的诗更以其反僵化的突围意识、"边缘"的移民史观和创作主体性、对"诗的故乡"的呵护等,呈现出南洋新生代的创作追求。他的典律构建视野的扩大,更意味着文学史将接纳新生代,而且是以改变自身的根本性格局来接纳他们。     

Assessing direct and indirect seasonal decomposition in state space

The problem of whether seasonal decomposition should be used prior to or after aggregation of time series is quite old. We tackle the problem by using a state-space representation and the variance/covariance structure of a simplified one-component model. The variances of the estimated components in a two-series system are compared for direct and indirect approaches and also to a multivariate method. The covariance structure between the two time series is important for the relative efficiency. Indirect estimation is always best when the series are independent, but when the series or the measurement errors are negatively correlated, direct estimation may be much better in the above sense. Some covariance structures indicate that direct estimation should be used while others indicate that an indirect approach is more efficient. Signal-to-noise ratios and relative variances are used for inference.     

高职院校专业和课程体系研究与改革探索——以广州城市职业学院为例

新组建的高职院校广州城市职业学院，基于“大平台、强专业、多方向、模块化”的人才培养思路进行了专业和课程体系改革。经过三年多的研究与实践，专业和课程体系得到了优化，教学质量得到了较大提高，为学校建设“迎评创示范”建设做出了贡献。     

论民商法原则对企业立法的规制

文章探讨了民商法原则对企业立法的规制.企业作为独立市场主体资格具有正常的行为方式,企业的行为必须是自益行为、自主行为和与企业组织形式相应的行为,国家管理不能取代社会调节功能,民事责任对于企业行为规制的基础性作用不容忽视.     

A Multi-National Study of Interparental Conflict,Parenting, and Adolescent Functioning

Abstract

This study assessed the associations between interparental conflict (IPC), parenting, and individual functioning among data gathered from school-going adolescents in Bangladesh, China, India, Bosnia, Germany, Palestine, Colombia, United States and three ethnic groups within South Africa. Specifically, we tested the validity of the spillover dynamic found in much research in the U.S., whereby marital conflict spills over into parenting and into the psychological and social functioning of children and adolescents. Previous analyses of these same data showed complete invariance in the linkages between parenting and adolescent functioning. This study thus provided a meaningful extension to the substantive literature on family processes. We followed recommendations within cross-cultural psychology to “transport and test” models validated in one culture to other cultures as an initial step in systematic comparative research. The findings revealed substantial invariance across the samples in documenting significant direct and indirect associations. Similar to prior research in the U.S., IPC was associated with youth outcomes directly, and more often indirectly, via parenting.     

The Late-Life Divorced

This study on divorce and the elderly includes a secondary analysis of data taken from Current Population Reports (CPR) and from The National Survey of Families and Households (NSFH). Age specific divorce prevalence rates calculated using the CPR, suggests an increase in the proportion of elderly divorced persons over the last 15 years, with the proportion of divorced women being greater than that of divorced men. Findings from the analysis of NSFH data suggests that women were more likely to turn to others for emotional support during separation than were men. Older women were more likely to than older men, The younger were more likely to than the older. Older women had better adjustment scores and overall happiness than did older men.     

A Phenomenological Study of Postdivorce Adjustment in Midlife

Today, 50% of all U.S. marriages are expected to end in divorce, with the majority of the divorces being granted to individuals between the ages of 45 and 54. Gaining an understanding of the lived experience of postdivorce adjustment as seen in midlife was the aim of this study. A phenomenological research design was used. The themes that emerged from the data included time, emotional pain, changes in postdivorce parenting, and a sense of starting over. The clinical implications of this study suggest that obtaining an understanding of the postdivorce adjustment experience might help mental health practitioners enhance care for divorced individuals, divorcing couples, and their family members.