Latent transition models with latent class predictors: attention deficit hyperactivity disorder subtypes and high school marijuana use

Summary.  Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder which is most often diagnosed in childhood with symptoms often persisting into adulthood. Elevated rates of substance use disorders have been evidenced among those with ADHD, but recent research focusing on the relationship between subtypes of ADHD and specific drugs is inconsistent. We propose a latent transition model (LTM) to guide our understanding of how drug use progresses, in particular marijuana use, while accounting for the measurement error that is often found in self-reported substance use data. We extend the LTM to include a latent class predictor to represent empirically derived ADHD subtypes that do not rely on meeting specific diagnostic criteria. We begin by fitting two separate latent class analysis (LCA) models by using second-order estimating equations: a longitudinal LCA model to define stages of marijuana use, and a cross-sectional LCA model to define ADHD subtypes. The LTM model parameters describing the probability of transitioning between the LCA-defined stages of marijuana use and the influence of the LCA-defined ADHD subtypes on these transition rates are then estimated by using a set of first-order estimating equations given the LCA parameter estimates. A robust estimate of the LTM parameter variance that accounts for the variation due to the estimation of the two sets of LCA parameters is proposed. Solving three sets of estimating equations enables us to determine the underlying latent class structures independently of the model for the transition rates and simplifying assumptions about the correlation structure at each stage reduces the computational complexity.     

郭店楚简《成之》等篇杂志

《郭店楚墓竹简》自从1998年问世后,一直引起中国内外学者的关注,成为研究先秦文字、历史、思想等领域的热门对象。然由于此批竹简的复杂性,再加上研究时间不长,因而尚有许多基本问题有待解决,而这些问题又是与竹简内容的正确理解息息相关的。如果郭店楚简几篇儒家逸书中的部分问题能够解决,便能够对其思想内涵及历史意义达到更进一步的认识。对《成之》篇作两处简序上的调整及对某些字提出新的读法后,便突显出了其中“恒”、“疾”、“终”的进阶概念,关于圣人对善道之“不拾”观念也可以有更深的理解。另外,对《唐虞之道》作简序调整,对《六德》中“多”字给新的解释,涉及问题虽小,但给先秦思想史研究带来的意义不可低估。     

The myth of the “data‐driven” society: Exploring the interactions of data interfaces,circulations, and abstractions

The prominence of data and data technologies in society, such as algorithms, social media, mobile technology, and artificial intelligence, have heralded numerous claims of the revolutionary potential of these systems. From public policy, to business management, to scientific research, a “data‐driven” society is apparently imminent—or currently happening—where “objective” and asocial data systems are believed to be comprehensively improving human life. Through a review of existing sociological literature, in this article, we critically examine the relationship between data and society and propose a new model for understanding these dynamics. “Using the concept of the informatic,” we argue the relationship between data and society can be understood as representing the interaction of several different social trends around data; that of data interfaces (that connect individuals to digital contexts), data circulation (trends in the movement and storage of data), and data abstraction (data manipulation practices). Data and data technologies are founded to be entwined and embedded in numerous social relationships, and while not all are fair and equitable relationships, there is ample evidence of the deeply social nature of data across many streams of social life. Our three‐part informatic framework allows these complex relationships to be understood in the social dynamic through which they are witnessed and experienced.     

The home visit in child protection social work: Emotion as resource and risk for professional judgement and practice

This article conceptualises the role of emotion in social work home visits. It draws on findings from a qualitative study of initial child protection home visits in the United Kingdom. The research used narrative interviews and focus groups to examine how emotions arising from visits were registered in social workers' narratives. These visits were often challenging; social workers needed to manage their own emotions and those of the family, while at the same time investigating concerns and assessing need. This article identifies seven key emotional experiences associated with the home visit from the perspective of the social worker: going into the unknown; being intrusive; being disliked; fear of harm to self; fear of causing or allowing harm; pain, disgust, and distress; and “absorbing” emotion. It is argued that emotion plays a central role in home visiting and that professionals' emotional responses have important implications for the way they make sense of, and manage, home visits. Emotion is therefore conceptualized as both a potential resource and risk for social workers' professional judgement and practice.     

Repairing the nest: A psychodynamic developmental approach to clients with severe behavior disorders

In this article, the authors explicate concepts from psychodynamic developmental theory that can foster affirmative assessment and intervention with clients who have developmental disabilities and present severe behavior disorders. A case example illustrates how making bonding the primary goal of intervention appears to facilitate positive behavior change in these clients while reducing feelings of helplessness and discouragement in their caregivers.     

The Career-Personal Dichotomy: Perceptual Reality,Practical Illusion,and Workplace Integration

The implicit definitions we give to career and personal counseling reflect a dichotomy between the two areas of research and practice. The field's research focus and counseling trainees' early practice experience probably reinforce the idea that career counseling is prototypically concerned with young adult career choice. A case study of targeted coaching in business is presented to illustrate how career and personal issues are intertwined in adult career adjustment.     

Modeling Two-state Disease Processes with Random Effects

Many chronic medical conditions are manifested by alternating sojourns in symptom-free and symptomatic states. In many cases, in addition to their relapsing and remitting nature, these conditions lead to worsening disease patterns over time and may exhibit seasonal trends. We develop a mixed-effect two-state model for such disease processes in which covariate effects are modeled multiplicatively on transition intensities. The transition intensities, in turn, are functions of three time scales: the semi-Markov scale involving the backward recurrence time for the cyclical component, the Markov scale for the time trend component, and a seasonal time scale. Multiplicative bivariate log-normal random effects are introduced to accommodate heterogeneity in disease activity between subjects and to admit a possible negative correlation between the transition intensities. Maximum likelihood estimation is carried out using Gauss-Hermite integration and a standard Newton-Raphson procedure. Tests of homogeneity are presented based on score statistics. An application of the methodology to data from a multi-center clinical trial of chronic bronchitis is provided for illustrative purposes.     

Who is responsible for household tasks in long term marriages of the “young-old” elderly?

Little is known about the way in which golden anniversary couples divide the responsibility for household tasks. This article examines the division of responsibility for 12 households tasks within a sample of 18 couples. At least one partner is under 75 years of age, the findings indicate that these young-old couples have developed interdependent, gender differentiated divisions of household tasks, although they share several tasks. There is congruence between what they expect and how they actually divide the responsibility for household tasks.