A biclustering algorithm for binary matrices based on penalized Bernoulli likelihood

We propose a new biclustering method for binary data matrices using the maximum penalized Bernoulli likelihood estimation. Our method applies a multi-layer model defined on the logits of the success probabilities, where each layer represents a simple bicluster structure and the combination of multiple layers is able to reveal complicated, multiple biclusters. The method allows for non-pure biclusters, and can simultaneously identify the 1-prevalent blocks and 0-prevalent blocks. A computationally efficient algorithm is developed and guidelines are provided for specifying the tuning parameters, including initial values of model parameters, the number of layers, and the penalty parameters. Missing-data imputation can be handled in the EM framework. The method is tested using synthetic and real datasets and shows good performance.     

Graphical methods for comparing confounding in two or more designs

In many circumstances it is necessary to design an experiment with partial confounding of parameter estimates. In this situation, one would like to have tools to assess and compare candidate designs graphically. In this paper we discuss two graphical representations of design properties, and illustrate their application with two examples.     

Web-Enhanced Preservice Training for Prospective Resource Parents: A Randomized Trial of Effectiveness and User Satisfaction

ABSTRACT

Traditionally, prospective resource parents must attend all preservice training in person. Although live sessions are necessary for screening applicants, instructional portions of training could be enhanced by Web-based sessions. This pilot study compares the effectiveness of online and classroom versions of one session from a widely used preservice training program. Ninety-two individuals enrolled in the program in two states were randomly assigned to a treatment group that viewed an online version of the class on child abuse and neglect or to a comparison group that took the same class in person. Written questionnaires were completed before and after the class. Significant group differences on knowledge of child maltreatment and empathy toward birth parents plus high user satisfaction were hypothesized. Analysis of covariance results showed the online training was more effective than the live training at increasing knowledge. Multivariate analysis of covariance findings on empathy were not significant but trended toward greater empathy for the online group. Feedback indicated high satisfaction with the online course. The finding that online instruction is more effective than live instruction has positive implications for practice, because Web-based training offers advantages like standardizing instruction, cutting agency and trainee costs, and providing greater flexibility.     

Ageing Society Issues in Korea*

Korean society is facing unprecedentedly higher population ageing, particularly in the first half of the 21st century. The implications of population ageing have a much wider effect than the welfare of the elderly. From a broader and long‐term perspective, understanding population ageing may require a new paradigm. Korea has attempted to model its policies for ageing society on those of advanced welfare states, but as these no longer seem viable, Korean policy‐makers are searching for more effective and efficient measures to deal with its rapid ageing population. Reflecting a broader and long‐term perspective, the Korean government recently produced a comprehensive national policy plan to deal with the consequences of rapid population ageing. This article outlines the phenomenon of population ageing in Korea and the recent development of national policies for population ageing, describing the Korean comprehensive national policy plan for responding to it and examining major issues and problems related to developing and implementing the plan. This article finally suggests a new, age‐integrated social system approach to an ageing society.     

Inside the blogosphere: A taxonomy and framing analysis of abortion weblogs

This study analyses weblog abortion-related content sampled via a search and snowball method. When weblogs located inside of established media Web sites and other weblogs are compared, they are equivalent in the use of advocacy versus objectivist frames. Media weblog posts contain a political frame more frequently than non-media weblog posts do. In terms of diversity of frame, media weblogs employ more frames in their stories. Various explanations for these findings are offered in the context of current abortion-related content patterns.     

Heterogeneity in Parent‐reported Social Skill Development in Early Elementary School Children

Despite known risks associated with aberrant social skill development, there has been a relative dearth of literature on typical developmental changes in social skills over time. In this study, we examine systematic changes in social skills from kindergarten (typical age of 5–6 years) to third grade (typical age of 8–9 years), and focus on systematic heterogeneity across these developmental trajectories. Data came from the National Head Start—Public School Early Childhood Transition Demonstration Project (N = 6964). Mixture models provide evidence for multiple classes of individuals representing heterogeneity in the development of social skills. Classes were defined as a majority class (whose trajectories remained relatively stable over time), an increasing class (whose trajectories increased at a faster rate than the majority class), and a decreasing class (whose trajectories decreased at a faster rate than the majority class). Developmental trends accounted for a substantial proportion of the variance in social skill components. Implications and limitations of the study are discussed.     

Minority comparison model: Effects of Whites’ multiracial evaluation on symbolic racism and racialized policy preferences

Most Racial Studies primarily focus on African Americans without paying attention to nonblack minorities, and it fails to capture recent increase in racial diversity. Based on previous theories and empirical findings, we propose a new model, minority comparison model, which accounts for theoretical shortcomings in Racial Studies. This model (1) captures psychological processes that compare blacks and nonblacks, and (2) explores the effects of whites’ multiracial evaluation on racialized policy preferences. Drawing on a 2008 national representative sample, this study finds that whites who have positive stereotype of nonblacks (e.g., Hispanics and/or Asians) but negative stereotype of blacks show substantially higher symbolic racism and stronger opposition to Affirmative Action, whereas whites who have positive stereotype of blacks but negative stereotypes of nonblacks have stronger opposition to expansive immigration policy. Our study offers new ways of understanding and accounting for symbolic racism in modern context, and shows how whites’ preferences in racialized policies are influenced by multiracial evaluation.     

Social Activity,School-related Activity,and Anti–substance Use: Media Messages on Adolescent Tobacco and Alcohol Use

In this article, we present the effects of three hypothesized protective factors—social activities, school-related activities, and anti–substance use media messages—on adolescent tobacco and alcohol use. Data were drawn from the “Monitoring the Future” research project, which was conducted by the Institute for Social Research at the University of Michigan. The sample included 2,551 twelfth-grade students. The results of the structural equation model showed that exposure to media anti-drug messages had an indirect negative effect on tobacco and alcohol use through school-related activity and social activity. The results suggest that comprehensive ecological interventions encompassing media, family, and school can increase the preventive effects of adolescent's substance use.