Learning from a lot: Empirical Bayes for high‐dimensional model‐based prediction

Empirical Bayes is a versatile approach to “learn from a lot” in two ways: first, from a large number of variables and, second, from a potentially large amount of prior information, for example, stored in public repositories. We review applications of a variety of empirical Bayes methods to several well‐known model‐based prediction methods, including penalized regression, linear discriminant analysis, and Bayesian models with sparse or dense priors. We discuss “formal” empirical Bayes methods that maximize the marginal likelihood but also more informal approaches based on other data summaries. We contrast empirical Bayes to cross‐validation and full Bayes and discuss hybrid approaches. To study the relation between the quality of an empirical Bayes estimator and p, the number of variables, we consider a simple empirical Bayes estimator in a linear model setting. We argue that empirical Bayes is particularly useful when the prior contains multiple parameters, which model a priori information on variables termed “co‐data”. In particular, we present two novel examples that allow for co‐data: first, a Bayesian spike‐and‐slab setting that facilitates inclusion of multiple co‐data sources and types and, second, a hybrid empirical Bayes–full Bayes ridge regression approach for estimation of the posterior predictive interval.     

“Migrant Capital” and Domestic Work: Labour Trajectories of Immigrant Women in Spain

This article analyses the labour trajectory of migrant women in domestic service. The research considers women's working conditions upon arrival, or their “migrant capital” (i.e. their human, social and economic capital) as the defining factors in their labour trajectories. The study, conducted on a sample of migrant women in domestic service, reveals the different value each type of capital has at each stage of a labour trajectory. The social network is the core capital in their first job. Nevertheless, the key factors in labour mobility are human capital and a household's financial needs. The processes of administrative regularization and family reunification prompt far‐reaching changes in these women's labour trajectories. Finally, labour trajectories during the economic crisis have been shaped by financial needs, leading to a decapitalization of the human capital acquired, with even legal status surrendering its value.     

Urban ecosystem Services in Latin America: mismatch between global concepts and regional realities?

Urban Ecosystems - Latin America and the Caribbean (LAC) is one of the most urbanized and biologically diverse regions in the world but is often characterized by weak environmental governance and...     

Use of Experiential Learning,Reflective Writing,and Metacognition to Develop Cultural Humility Among Undergraduate Students

This study discusses the use of experiential learning, reflective writing, and metacognition to develop cultural humility among undergraduate students enrolled in a social and economic justice course. Students participated in an activity that challenged them to learn about people who may have different social identities and experiences from their own such as attending a service in a religion different from their own. Then students wrote a reflective essay in which they used the margin of the paper as a safe space to write anything that came to mind during the writing process. A thematic analysis of students’ comments suggests that students used the space to examine their emotions, seek understanding of self and others, and recognize their privilege.     

公共物品公共性的变化及其有效提供

在一端为公共物品 ,一端为私人物品的物品序列中 ,同一物品的相对位置会因为排他性技术水平的不同而表现出不确定性 ,导致物品公共性的不断变化。这种位置变化决定了对于公共物品提供者的选择 ,改变了政府提供公共物品的传统观点。据此 ,公共物品提供的理论基础应是公共物品提供的经济发展观 :依据公共物品在不同阶段特性的改变选择不同的提供者。这就为非政府组织、私人提供公共物品准备了条件。在中国城市大力引进非政府组织提供城市各种公共物品的同时 ,广大农村公共物品的提供在现阶段只能由政府来提供     

大学英语专业教学中输入输出探究

语言习得过程其实质就是语言的输入输出过程,其质量的高低直接影响其成败。文本结构理论介入基础英语课堂教学和学生的英语学习在一定程度上有助于改变课堂上以教师为中心的教学模式,丰富课堂教学方法,调动学生英语学习的积极性和主动性,有利于学生思维能力和创新能力的培养,对提高学生课外语言输入输出的质和量有一定的促进作用。     

Dealing with Migrants in the Central Mediterranean Route: A Legal Analysis of Recent Bilateral Agreements Between Italy and Libya

Dealing with the current flow of migrants flocking to the shores of southern European countries remains high on the international agenda. At the end of 2016, 276,957 migrants were waiting in Libya to cross the sea. Many of them were subject to human rights violations and abuses such as arbitrary detention, torture, unlawful killings, sexual exploitation and even slavery (IOM, 2017). The international response has been, so far, insufficient and new ideas and practices are urgently needed. After providing an overview of the legal framework and of the efforts carried out by the relevant international and regional organizations, this article focuses on recent treaties concluded between Italy and Libya, and argues that the new bilateral agreements represent an example of how States are responding to this challenge in an attempt to strike a balance between the need to strengthen the protection of migrants’ rights and the necessity to guarantee the security of national borders.     

Do Associations Between Pleasure Ratings and Condom Use During Penile–Vaginal Intercourse Vary by Relationship Type?: A Study of Canadian University Students

Research suggests the relationship between pleasure and condom use during penile–vaginal intercourse (PVI) is associated with relationship status. This online study examined pleasure ratings and condom use at last PVI, stratifying by partner type, among a national sample of Canadian university students. Participants were 715 undergraduates (60.7% women, 39.3% men) who reported on their most recent sexual experience. Condom use decreased with level of relationship commitment, whereas ratings of pleasure increased. Overall, participants were more likely to rate their most recent PVI as Very pleasurable when condoms were not used compared to when condoms were used. However, when stratified by partner type, these differences largely disappeared. For women, with one exception, there were no differences in pleasure between PVI with and without condoms across most partner-type categories. Women in committed dating relationships were more likely to report their last PVI as very pleasurable if condoms were not used than women in these same relationships who had used condoms. Across relationship categories, men who did and did not use condoms did not differ in terms of their pleasure ratings. The results of this study suggest relationship context should be taken into account when assessing condom use experiences.     

Forward irrelevance

We investigate how to combine marginal assessments about the values that random variables assume separately into a model for the values that they assume jointly, when (i) these marginal assessments are modelled by means of coherent lower previsions and (ii) we have the additional assumption that the random variables are forward epistemically irrelevant to each other. We consider and provide arguments for two possible combinations, namely the forward irrelevant natural extension and the forward irrelevant product, and we study the relationships between them. Our treatment also uncovers an interesting connection between the behavioural theory of coherent lower previsions, and Shafer and Vovk's game-theoretic approach to probability theory.     

Transformed generalized linear models

The estimation of data transformation is very useful to yield response variables satisfying closely a normal linear model. Generalized linear models enable the fitting of models to a wide range of data types. These models are based on exponential dispersion models. We propose a new class of transformed generalized linear models to extend the Box and Cox models and the generalized linear models. We use the generalized linear model framework to fit these models and discuss maximum likelihood estimation and inference. We give a simple formula to estimate the parameter that index the transformation of the response variable for a subclass of models. We also give a simple formula to estimate the r$r$th moment of the original dependent variable. We explore the possibility of using these models to time series data to extend the generalized autoregressive moving average models discussed by Benjamin et al. [Generalized autoregressive moving average models. J. Amer. Statist. Assoc. 98, 214–223]. The usefulness of these models is illustrated in a simulation study and in applications to three real data sets.