Robust gene–environment interaction analysis using penalized trimmed regression

ABSTRACT

In biomedical and epidemiological studies, gene–environment (G–E) interactions have been shown to importantly contribute to the etiology and progression of many complex diseases. Most existing approaches for identifying G–E interactions are limited by the lack of robustness against outliers/contaminations in response and predictor spaces. In this study, we develop a novel robust G–E identification approach using the trimmed regression technique under joint modelling. A robust data-driven criterion and stability selection are adopted to determine the trimmed subset which is free from both vertical outliers and leverage points. An effective penalization approach is developed to identify important G–E interactions, respecting the ‘main effects, interactions’ hierarchical structure. Extensive simulations demonstrate the better performance of the proposed approach compared to multiple alternatives. Interesting findings with superior prediction accuracy and stability are observed in the analysis of The Cancer Genome Atlas data on cutaneous melanoma and breast invasive carcinoma.     

Likelihood Inference for Unions of Interacting Discs

Abstract. This is probably the first paper which discusses likelihood inference for a random set using a germ‐grain model, where the individual grains are unobservable, edge effects occur and other complications appear. We consider the case where the grains form a disc process modelled by a marked point process, where the germs are the centres and the marks are the associated radii of the discs. We propose to use a recent parametric class of interacting disc process models, where the minimal sufficient statistic depends on various geometric properties of the random set, and the density is specified with respect to a given marked Poisson model (i.e. a Boolean model). We show how edge effects and other complications can be handled by considering a certain conditional likelihood. Our methodology is illustrated by analysing Peter Diggle's heather data set, where we discuss the results of simulation‐based maximum likelihood inference and the effect of specifying different reference Poisson models.     

以职业能力培养为目标的视听说互动教学模式研究与实践

互动教学模式应用于视听说教学，用先进的教学理念培养学生的英语听说技能与职业能力。     

休闲价值观与世界一流大学

广义的休闲价值观是指休闲本身的价值、休闲对个体生命的意义，尤其指休闲与工作之间的辩证关系。世界一流大学是具有世界一流师资并拥有自由精神等特征的大学。休闲与学校的关系源远流长，在古希腊时期，休闲是人生的重要目的，也是教育的目的，休闲与学校有着密切联系。随着社会发展和历史变迁，休闲的价值和地位也经过了曲折起伏的过程，休闲与学校的关系也需要重新梳理。近代休闲具备的自由、社会交往和创造性等特征仍使之与学校特别是世界一流大学有密切关系，休闲理念和价值观也对世界一流大学建设具有重要的积极意义。     

The Presentation of Avatars in Second Life: Self and Interaction in Social Virtual Spaces

What do interactions in virtual spaces suggest about everyday life in the digital age? How do interactions in virtual spaces shape everyday life in the digital age? Guided by hypermodern theory, I conduct participant observation in the social virtual world Second Life to provide tentative answers to those questions. I suggest that Second Life is both a social psychological playground where participants enjoy individualistic fantasies and a virtual community where they collaborate on collective projects. When people define the virtual as real, it is real in its consequences. Accordingly, social virtual spaces such as Second Life offer sociologists unique opportunities for research, education, intervention, and hence the development of a virtual imagination.     

Increasing the effectiveness of time-use survey with qualitative methods: The analysis of time–space interaction

Time-use surveys have been rich data sources in many countries for a long time. Turkey was among the countries that realized the potential of time-use surveys quite late and completed the first national survey in 2006. Despite its importance for a wide range of issues and applications, the first survey has flaws in design, which reduce its effectiveness and reliability. This is mostly due to disregarding cultural factors while tracking the methodology of European examples. This study aims to propose more appropriate methods of gathering time-use data in the Turkish context through a field survey in Ankara, the capital city. A mixed methodology that combines quantitative and qualitative methods effectively was applied and used to enrich data. The influence of space use was stressed and leisure activities were utilized to exemplify the use and benefits of mixed methods.     

Parents' perceptions of their children in a context of shared political uncertainty

The study describes the differences and similarities between parents’ feelings and their perception of their children’s feelings in a politically uncertain situation. The study focuses on Israeli families living in Judaea and Samaria (the West Bank) during two periods: the Intifada and the post‐Oslo Agreements years during the first phase of the peace process with the Palestinians. The research combines qualitative and quantitative methods. The results show that most of the feelings evoked by the uncertainty are negative emotions, such as fear, anger, hate, the desire for revenge, and avoidance. These emotions are experienced by parents and, according to the parents’ perceptions, by their children as well. In addition to the correlation between parents’ own experiences and their appraisal of their children’s, the children were perceived as having more negative feelings than the parents. Systemic analysis of the results indicates that the children are often a channel for expression of their parents’ emotions. Based on this finding, suggestions are made regarding intervention with children that takes family processes into account. Some direction for applying the findings of this specific study in other contexts of shared political uncertainty, such as Northern Ireland, are suggested.     

Pragmatics of Self- and Other-Reference in Young Children

During the first years of life, children come to understand and talk about a self separate from others. This study examined self- and other-reference and communicative intents expressed by children and parents in dyadic interaction at 14, 20 and 32 months. Research questions included whether children's early use of self- and other-reference pronouns occurred for expression of particular communicative intents, how use changed with age, and whether parent and child pragmatic expressions of self and other were similar. Results showed that children's early explicit reference to self tended to take the form of I rather than me/my/mine, and was used primarily in making statements about their intended actions, in making requests or proposals to their parents and in stating propositions about the world around them. Children during this developmental period were only beginning to refer to the present other with the pronoun you and these instances occurred primarily in making requests or proposals. Despite age-related increases in pronominal forms and intents, a small set of intents continued to provide the context for most self- and other-reference pronouns. In the communicative contexts in which they explicitly refer to self and other, children did not appear to exclusively mirror those which were observed in parental speech.     

外语课堂互动中的修正性反馈：教师信念与课堂教学行为关系研究

运用个案研究法，聚焦于三位英语专业精读课教师的修正性反馈教学信念和课堂行为，结果发现：不同教师所持的教学信念互不相同。他们的课堂教学行为也存在巨大差异；同一教师持有内部相矛盾的信念；由于教学环境和教师所调用的知识类型的不同。同一教师的教学信念和教学行为之间虽具有一定的联系，但二者差异很大。     

A Note on the Lower Bounds on Maximum Number of Clear Two-Factor Interactions for (2 m−p III) and (2 m−p IV) Designs

ABSTRACT

In the reliability analysis of mechanical repairable equipment subjected to reliability deterioration with operating time, two forms of the non-homogeneous Poisson processes, namely the Power-Law (PL) and the Log-Linear (LL) model, have found general acceptance in the literature. Inferential procedures, conditioned on the assumption of the PL or LL model, underestimate the overall uncertainty about a quantity of interest because the PL and LL models can provide different estimates of the quantity of interest, even when both of them adequately fit the observed data. In this paper, a composite estimation procedure, which uses the PL and LL models as competing models, is proposed in the framework of Bayesian statistics, thus allowing the uncertainty involved in model selection to be considered. A model-free approach is then proposed for incorporating technical information on the failure mechanism into the inferential procedure. Such an approach, which is based on two model-free quantities defined irrespectively of the functional form of the failure model, prevents that the prior information on the failure mechanism can improperly introduce prior probabilities on the adequacy of each model to fit the observed data. Finally, numerical applications are provided to illustrate the proposed procedures.