Modified genetic algorithm-based clustering for probability density functions

This article modifies two internal validity measures and applies them to evaluate the quality of clustering for probability density functions (pdfs). Based on these measures, we propose a new modified genetic algorithm called GA-CDF to establish the suitable clusters for pdfs. The proposed algorithm is tested by four numerical examples including two synthetic data sets and two real data sets. These examples illustrate the superiority of proposed algorithm over some existing algorithms in evaluating the internal or external validity measures. It demonstrates the feasibility and applicability of the GA-CDF for practical problems in data mining.     

Multiple comparisons in two-factor testing of psychophysical thresholds by the delta test method

We propose an algorithm of multiple comparisons in two-factor testing of psychophysical thresholds. We use logistic regression combined with guessing rate and adopt the step-down procedure with Ryan–Einot–Gabriel–Welsch (REGW) significance levels for multiple test. We test hypotheses of main effects and interaction in two-factor problem by using the delta test statistics.     

Statistical analysis of dependent competing risks model in accelerated life testing under progressively hybrid censoring using copula function

This article considers statistical analysis of dependent competing risks model from Weibull distribution in accelerated life testing, in which copula function is used to examine the dependence structure between competing failure modes. We derive the maximum likelihood estimates, the approximate, and Bootstrap confidence intervals of the parameters. The effects of different dependence structures on the estimates of parameters are investigated. The simulation is given to compare the performance of the estimates when the competing failure modes are dependent with those when the failure modes are independent. Finally, one dataset was used for illustrative purpose in conclusion.     

Bootstrap methods for multivariate hypothesis testing

The nonparametric and parametric bootstrap methods for multivariate hypothesis testing are developed. They are used to approximate the null distribution of the test statistics proposed by Duchesne and Francq (2015 Duchesne, P., Francq, C. (2015). Multivariate hypothesis testing using generalized and {2}-inverses—with applications. Statistics 49:475–496.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]), resulting in bootstrap testing procedures. In the problem of testing for the mean vector of a multivariate distribution, the asymptotic validity of the bootstrap methods is proved. The finite sample performance of the new solutions is demonstrated by means of Monte Carlo simulation studies. They indicate that for small-sample size, the bootstrap tests provide a better finite sample properties than the asymptotic tests considered by Duchesne and Francq (2015 Duchesne, P., Francq, C. (2015). Multivariate hypothesis testing using generalized and {2}-inverses—with applications. Statistics 49:475–496.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]).     

Sexual orientation differences in HIV testing motivation among college men

Objective: To investigate sexual orientation differences in college men's motivations for HIV testing. Participants: 665 male college students in the Southeastern United States from 2006 to 2014. Methods: Students completed a survey on HIV risk factors and testing motivations. Logistic regressions were conducted to determine the differences between heterosexual men (HM) and sexual minority men (SMM). Results: SMM were more motivated to get tested by concern over past condomless sex, while HM were more often cited supporting the testing program “on principle” and wanting a free t-shirt. SMM and HM differed in behaviors that impact HIV risk and other demographics. However, differences in testing motivation by concern over past condomless sex or wanting a free t-shirt persisted when controlling for these demographic and behavioral differences. Conclusions: Appropriately designed HIV prevention interventions on college campuses should target SMM's distinct concern over past condomless sex as a testing motivation.     

犯罪记忆心理的可测性与局限性

中国的心理测试技术,是运用现代心理学、犯罪心理学和实验心理学原理以及神经心理学、生物电子学等研究成果,通过专用测试仪器软硬件和智能化计算机系统,同时同步记录人的多项心理生物反映指标,进而评判心理痕迹对应相关程度的实验心理技术。心理测试中心近20年犯罪心理测试的研究成果、以及经过直接参与办理全国各地600多起重特大疑难案件的实践、和经过对近万人实案测试图谱的评判分析研究,得出的结论是:违法犯罪人在经历过违法犯罪事件之后的记忆违法犯罪心理痕迹是可测的。这项技术在辅助刑侦工作方面有着很大的作用,但同样,我们也要看到它的局限性。     

我国遗传资源获取与惠益分享的立法建议

随着生物多样性的保护和生物技术的高速发展,遗传资源的保护问题也日渐凸显,遗传资源的获取与惠益分享所涉及的法律问题渐渐走进了人们的视野,尤其是在《名古屋议定书》之后,对于我国的遗传资源保护法律与管理体制又提出了新的挑战,解决遗传资源的获取与惠益分享的法律问题已经刻不容缓,必须尽快完善我国的遗传资源获取与惠益分享的法律制度,以最大限度的保护遗传资源并实现最佳收益。     

快速遗传算法研究

提出了一种称为广义自适应遗传算法的快速遗传算法,它首先产生均匀分布的初始种群,其次根据种群模式的状况决定是否引入“高品质”移民,最后自适应地进行交换和变异运算。其搜索性和全局收敛性比现有的许多遣传算法都有明显的改善,并通过仿真说明了该改进遣传算法的有效性。