Change Point Estimation of Multivariate Linear Profiles Under Linear Drift

In this paper, maximum likelihood estimators (MLE) for both step and linear drift changes in the regression parameters of multivariate linear profiles are developed. Performance of the proposed estimators is compared under linear drift changes in the regression parameters when a combined MEWMA and Chi-square control charts method signals an out-of-control condition. The effect of smoothing parameter of MEWMA control charts, missing data, and multiple drift changes on the performance of the both estimators is also evaluated. The application of the proposed estimators is also investigated thorough a numerical example resulted from a real case.     

关于社会主要矛盾中需求变化的分析

社会主义初级阶段的主要矛盾仍然是“人民日益增长的物质文化需要同落后的社会生产之间的矛盾”,但“人民日益增长的物质文化需要”的内容和结构已经发生了新的变化,主要表现为公共消费品的匮乏。这一状况严重制约着社会主要矛盾的解决和社会主义发展目标的实现。政府应该从经济发展、民主法制等方面通过一定途径加以解决,以促进社会的全面进步。     

信息?噪音?泡沫?--现代金融学前沿问题综论

30多年来,关于证券市场信息效率的研究一直是现代金融学的焦点问题.有效市场假说从理性行为出发,得出证券价格总是可以充分反映可获得的信息,其价格等于其"内在价值",即预期未来现金流的折现价值.然而,从上个世纪80年代开始,这一假说受到了空前的质疑,首先是来自噪音学派关于交易成本的批评,随后是来自行为金融学关于有限套利和噪音交易等更为严厉的质疑.90年代末关于证券市场价格泡沫的研究又成为现代金融学备受关注的热门话题.     

Fusion Product Planning: A Market Offering Perspective*

Devices that integrate multiple functions together are popular in consumer electronic markets. We describe these multifunction devices as fusion products as they fuse together products that traditionally stand alone in the marketplace. In this article, we investigate the manufacturer's fusion product planning decision, adopting a market offering perspective that allows us to address the design and product portfolio decisions simultaneously. The general approach adopted is to develop and analyze a profit‐maximizing model for a single firm that integrates product substitution effects in identifying an optimal market offering. In the general model, we demonstrate that the product design and portfolio decisions are analytically difficult to characterize because the number of possible portfolios can be extremely large. The managerial insight from a stylized all‐in‐one model and numerical analysis is that the manufacturer should, in most cases, select only a subset of fusion and single‐function products to satisfy the market's multidimension needs. This may explain why the function compositions available in certain product markets are limited. In particular, one of the key factors driving the product portfolio decision is the margin associated with the fusion products. If a single all‐in‐one fusion product has relatively high margins, then this product likely dominates the product portfolio. Also, the congruency of the constituent single‐function products is an important factor. When substitution effects are relatively high (i.e., the product set is more congruent), a portfolio containing a smaller number of products is more likely to be optimal.     

The Differential and Contingent Impact of Concurrency on New Product Development Project Performance: A Holistic Examination*

This article comprehensively examines how the four facets of new product development (NPD) concurrency, consisting of process and product concurrency groupings, influence NPD project performance under the five contextual conditions of (i) location of product in family stream, (ii) project size, (iii) stage in the product life cycle, (iv) innovativeness of the product, and (v) predictability of market demand. Using data from a large sample of NPD projects in multiple industries, there is support for this hypothesized four‐faceted structure of concurrency, consisting of process and product concurrency groupings, thereby contributing new knowledge to the concurrency literature. All four facets of concurrency display a contingent impact on NPD project performance, even though individual effects vary according to the specific contextual variable under consideration. In particular, the process concurrency facet of dynamic iterative routines was universally effective across all five contextual variables, while the product concurrency facet of cross‐functional coordination was effective in significantly influencing at least one NPD project measure. This article also reports similar, but less strong, contingency patterns, with respect to the process concurrency facet of the implementation of downstream coordination and the product concurrency facet of the use of computer‐based integrated design tools. Theoretical and practical implications of our results are also offered.     

Managing Product Rollovers

We study the product rollover strategy decision, where a firm decides whether to phase out an old generation of a product to be replaced by a new with either a dual or single roll. Our model considers a final build of the old product and preannouncement of the new, and incorporates dynamic pricing and inventory decisions. We find that the optimal price path closely follows changes in reservation price curves for the two products over time. We also identify the drivers of the rollover strategy decision, finding that lower market risk (faster diffusion, higher market responsiveness to preannouncements) and higher performance improvement for the new generation are associated with the single roll strategy.     

境外所得税收综合限额抵免效应研究

境外所得税收抵免的计算虽是对外直接投资税收政策中一个简单环节,但不同的计算方法对ODI的影响也不同。国内学者普遍呼吁实行综合限额抵免,但政府基于税收以及东道国反应的考虑而迟迟未实行。研究表明综合限额抵免确实能够减轻投资者税负,达到激励ODI的作用,且在延期纳税条件下,政府顾虑的影响并不明显,因此我国还是应该变分国不分项限额抵免为综合限额抵免。     

Non-parametric Estimation of a Survival Function with Two-stage Design Studies

Abstract.  The two-stage design is popular in epidemiology studies and clinical trials due to its cost effectiveness. Typically, the first stage sample contains cheaper and possibly biased information, while the second stage validation sample consists of a subset of subjects with accurate and complete information. In this paper, we study estimation of a survival function with right-censored survival data from a two-stage design. A non-parametric estimator is derived by combining data from both stages. We also study its large sample properties and derive pointwise and simultaneous confidence intervals for the survival function. The proposed estimator effectively reduces the variance and finite-sample bias of the Kaplan–Meier estimator solely based on the second stage validation sample. Finally, we apply our method to a real data set from a medical device postmarketing surveillance study.     

面向产品全生命周期的保证成本预测系统

随着市场竞争日益激烈,产品保证成本预测所依赖的数据需要根据反馈情况不断更新,对产品整个生命周期中的保证成本预测进行集成管理显得十分重要。本文提出了基于网络、集成技术,等一系列预测方法和管理模式的保证成本预测系统,并介绍了其系统架构、实现的关键技术:浏览器技术、中间件技术、数据库技术及其功能实现方式。