Time filter

Source Type

Huang L.,Beihang University | Huang L.,Credit Card Center | Zhao J.,Beijing Normal University | Wang H.,Beihang University | And 2 more authors.
Computational Statistics and Data Analysis | Year: 2016

In functional data analysis (FDA), variable selection in regression model is an important issue when there are multiple functional predictors. Most of the existing methods are based on least square loss and consequently sensitive to outliers in error. Robust variable selection procedure is desirable. When functional predictors are considered, both non-data-driven basis (e.g. B-spline) and data-driven basis (e.g. functional principal component (FPC)) are commonly used. The data-driven basis is flexible and adaptive, but it raise some difficulties, since the basis must be estimated from data. Since least absolute deviation (LAD) loss has been proven robust to the outliers in error, we propose in this paper a robust variable selection with data-driven basis FPC and LAD loss function. The asymptotic results are established for both fixed and diverging p. Our results include the existing results as special cases. Simulation results and a real data example confirm the effectiveness of the proposed method. © 2016 Elsevier B.V. Source

Wang H.,Beihang University | Wang H.,Beijing Key Laboratory of Emergency Support Simulation Technologies for City Operations | Huang L.,Beihang University | Huang L.,Beijing Key Laboratory of Emergency Support Simulation Technologies for City Operations | Wang S.,Central University of Finance and Economics
Beijing Hangkong Hangtian Daxue Xuebao/Journal of Beijing University of Aeronautics and Astronautics | Year: 2016

Functional linear regression model has captured much attention in functional data analysis. By tools in semiparametric and nonparametric statistics, it is proposed to estimate the coefficients in generalized linear regression models with both multivariate scalar covariates and functional covariates. In this framework, the theory of generalized linear model is introduced, and the response variable is not required to be continuous random variable and may be discrete or attribute data, which widely broadens the application of functional linear model by solving the regression problem of predictors with mixed types of multivariate data and functional data. Besides, Logistic regression and Possion regression corresponding to categorical or discrete responses were emphasized, and a reweight algorithm for maximizing the log likelihood function was provided. In the procedure of estimation, functional principal component analysis and B spline were utilized, and the criterion to select the number of basis functions was suggested. The simulation results show that the proposed estimation and test methods are effective. © 2016, Beijing University of Aeronautics and Astronautics (BUAA). All right reserved. Source

Chen Y.-Z.,Beihang University | Zhao Q.-H.,Beihang University | Zhao Q.-H.,Beijing Key Laboratory of Emergency Support Simulation Technologies for City Operations
Xitong Gongcheng Lilun yu Shijian/System Engineering Theory and Practice | Year: 2015

Self-aid and mutual aid for affected areas immediately after disasters is essential in the rescue work. Emergency supplies distribution problem which considers the mutual aid among the affected areas is researched in this paper. The problem occurs in the period when the supplies cannot be transported to the affected areas immediately after natural disasters. A bi-objective optimization model with fairness constraint is constructed, with the first objective maximize delivery supplies and the second objective minimizing the maximum transport time among the affected areas. Besides, an improved differential evolution algorithm is proposed to solve the optimization model. And experimental results show the proposed algorithm is effective in the computation time and the quality of the solution. At the same time, the reasonability of the fairness is verified. Finally, the improved differential evolution algorithm is suitable for large scale problems and the relationship between the allowed transport time of relief supplies and area cooperation frequency is analyzed. This work has an important significance in theoretical and practical of attribution principles based self-aid and mutual aid management in natural disaster. © 2015, Systems Engineering Society of China. All right reserved. Source

Wang H.,Beihang University | Wang H.,Beijing Key Laboratory of Emergency Support Simulation Technologies for City Operations | Xia B.,Beihang University | Xia B.,Beijing Key Laboratory of Emergency Support Simulation Technologies for City Operations | Chen Z.,Beihang University
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2015

This paper studies cultural difference on team performance in a multiplayer online battle arena game called Defense of the Ancient 2(DOTA2). 37 international competition replays are acquired from the game platform of DOTA2 between Chinese teams and American teams. Though observing the replays, seven variables are brought up and paired data for each variable is obtained. Non-parametric test methods have been used to analyze the data, such as Wlicoxon test and Mood test. The result indicates some cultural differences in online games between two countries’ teams as following. Chinese teams are risk-avoiding while American teams are risk-taking. In addition, American teams show potential stronger masculinity than Chinese teams. © Springer International Publishing Switzerland 2015. Source

Wang L.,Beihang University | Wang L.,Beijing Key Laboratory of Emergency Support Simulation Technologies for City Operations | Lei C.,Beihang University | Xu Y.,China National Institute of Standardization | And 4 more authors.
Information Technology and Management | Year: 2014

In the small-world model, information nodes' positions are relatively ordered. However, information dissemination between nodes is unordered on the Internet. In this study, a product quality and safety information dissemination model on the Internet is proposed in terms of the characteristics of the scale-free model in the complex network. Using the simulation tests, we found that the information diffusion rate will speed up and the time needed for the system to reach the equilibrium will shorten when the spontaneous dissemination coefficient increases. Additionally, the scope of information coverage also increases as the system's size increases. However, the time of information diffusion needed to cover the maximum area does not change with the system's size. The media's influence has also been found to have an effect on the information dissemination. © 2014 Springer Science+Business Media New York. Source

Discover hidden collaborations