ECM-IS视角下移动政务APP用户持续使用意愿影响因素研究

随着“互联网+”时代的到来，移动政务APP快速发展，但也存在功能单一、满意度不高、用户持续使用意愿较低的问题，要促使其健康发展，必须重视用户的使用体验和使用意愿。本研究以ECM-IS模型理论为基础，构建了移动政务APP用户持续使用意愿影响因素模型，据此设计调查问卷并进行实证研究。研究结果显示，移动政务APP的系统质量是满足用户期望的重要因素，而用户感知对于提升用户的满意度以及促使持续使用具有重要的意义，其中，感知便利性和感知有用性的积极作用尤为明显。最后，从促使用户持续使用的角度，提出了完善移动政务APP系统功能、突出实用优势，兼顾趣味功能，以及重视用户感知、强调人文关怀等对策和建议。     

Price bias and common practice in option pricing

Generally, the semiclosed-form option pricing formula for complex financial models depends on unobservable factors such as stochastic volatility and jump intensity. A popular practice is to use an estimate of these latent factors to compute the option price. However, in many situations this plug-and-play approximation does not yield the appropriate price. This article examines this bias and quantifies its impacts. We decompose the bias into terms that are related to the bias on the unobservable factors and to the precision of their point estimators. The approximated price is found to be highly biased when only the history of the stock price is used to recover the latent states. This bias is corrected when option prices are added to the sample used to recover the states' best estimate. We also show numerically that such a bias is propagated on calibrated parameters, leading to erroneous values. The Canadian Journal of Statistics 48: 8–35; 2020 © 2019 Statistical Society of Canada     

Reducing sample size needed for cox-proportional hazards model analysis using more efficient sampling method

Abstract

In general, survival data are time-to-event data, such as time to death, time to appearance of a tumor, or time to recurrence of a disease. Models for survival data have frequently been based on the proportional hazards model, proposed by Cox. The Cox model has intensive application in the field of social, medical, behavioral and public health sciences. In this paper we propose a more efficient sampling method of recruiting subjects for survival analysis. We propose using a Moving Extreme Ranked Set Sampling (MERSS) scheme with ranking based on an easy-to-evaluate baseline auxiliary variable known to be associated with survival time. This paper demonstrates that this approach provides a more powerful testing procedure as well as a more efficient estimate of hazard ratio than that based on simple random sampling (SRS). Theoretical derivation and simulation studies are provided. The Iowa 65+ Rural study data are used to illustrate the methods developed in this paper.     

A class of additive transformation models for recurrent gap times

Abstract

The gap time between recurrent events is often of primary interest in many fields such as medical studies, and in this article, we discuss regression analysis of the gap times arising from a general class of additive transformation models. For the problem, we propose two estimation procedures, the modified within-cluster resampling (MWCR) method and the weighted risk-set (WRS) method, and the proposed estimators are shown to be consistent and asymptotically follow the normal distribution. In particular, the estimators have closed forms and can be easily determined, and the methods have the advantage of leaving the correlation among gap times arbitrary. A simulation study is conducted for assessing the finite sample performance of the presented methods and suggests that they work well in practical situations. Also the methods are applied to a set of real data from a chronic granulomatous disease (CGD) clinical trial.     

The arithmetic of outcome editing in financial and social domains

Outcome editing refers to a set of mental rules that people apply when deciding whether to evaluate multiple outcomes jointly or separately, which subsequently affects choice. In a large-scale online survey (n = 2062) we investigate whether individuals use the same outcome editing rules for financial outcomes (e.g., a lottery win) and social outcomes (e.g., a party with friends). We also test the role of numeric ability in explaining outcome editing. Our results show that people’s preferences for combining or separating events depend on whether those events are in the financial or the social domain. Specifically, individuals were more likely to segregate social outcomes than monetary outcomes, except for when all outcomes were negative. Moreover, numeric ability was associated with preferences for outcome editing in the financial domain but not in the social domain. Our findings extend the understanding of the arithmetic operations underlying outcome editing and suggest that people rely more on calculations when making choices involving multiple financial outcomes and more on feelings when making choices involving social outcomes.     

弹性力学课程在专业基础课教学中的教学与实践

通过对弹性力学课程教学过程的探讨，给出了适合我校的弹性力学课程教学过程，构建了弹性力学课程的新的教学方法和教学手段，效果良好，全面提高了弹性力学的教育水平和教学质量。     

电信运营商投资效益仿真研究——基于系统动力学视角

针对目前电信运营商投资效益分析方法单一的现状，依据电信运营商投资效益非线性、动态性等特征，运用系统动力学方法构建了电信运营商投资效益仿真模型，对电信运营商投资效益影响因素进行了仿真分析。结果表明网络设备延迟投入、综合造价等对投资效益影响较大，在此基础上，给出了电信运营商在针对投入产出水平和提升效益方面的建议。     

水质预报系统的MPI+OpenMP并行优化研究

OpenMP(Open Multi-Processing)能够在共享存储环境中获得理想的并行性能,MPI＋OpenMP混合并行编程模型更贴近于多核心集群的体系结构。在多核心集群上进行实验,混合模型相对串行程序可缩短95%的运算时间,加速比超过20。实验结果表明,该混合模型比纯MPI并行的系统具有更优的加速比和扩展性,是对纯MPI并行系统的一种改进。     

机械设计制造及其自动化专业人才培养模式的创新实践

在新的历史条件下,深化高等教育改革、提高专业人才培养质量,关键是必须改革和创新专业人才培养模式。围绕专业人才培养目标和基本要求,从制订专业人才培养方案、建立基于课程群的完整的人才培养课程体系、创新人才培养模式等方面,阐述了我校机械设计制造及其自动化专业进行综合改革的具体做法,这对其他高校相关专业的教学改革及人才培养,具有一定的启发。     

障碍研究论述与社会参与：无障碍、通用设计、能力与差异

障碍研究在过去40年的发展奠定了其对公共政策影响的基础。障碍者社会参与的责任逐渐由以往个人承担与调适，转向社会与国家承担。本文简述西方国家障碍研究的两个主要论述--社会模式与普同主义取向，对比这两个主要论述所衍生出的政策：由早期的无障碍设施到通用设计，至最近的能力取向。障碍者参与社会生活与活动是其基本权利的一部分，这项权利内涵具有积极性，需要政府与社会投入资源，改善外部社会结构与环境，使环境对障碍者更为友善，为其社会参与权利提供保障。