On the loss of information in conditional maximum likelihood estimation of item parameters

In item response models of the Rasch type (Fischer & Molenaar, 1995), item parameters are often estimated by the conditional maximum likelihood (CML) method. This paper addresses the loss of information in CML estimation by using the information concept of F-information (Liang, 1983). This concept makes it possible to specify the conditions for no loss of information and to define a quantification of information loss. For the dichotomous Rasch model, the derivations will be given in detail to show the use of the F-information concept for making comparisons for different estimation methods. It is shown that by using CML for item parameter estimation, some information is almost always lost. But compared to JML (joint maximum likelihood) as well as to MML (marginal maximum likelihood) the loss is very small. The reported efficiency in the use of information of CML to JML and to MML in several comparisons is always larger than 93%, and in tests with a length of 20 items or more, larger than 99%.     

Eating patterns and breakfast consumption in obese patients with binge eating disorder

This study examined eating patterns and breakfast consumption, and their relationships to weight and binge eating, in obese individuals with binge eating disorder (BED). One-hundred seventy-three consecutively evaluated men (n=46) and women (n=127) with BED were administered semi-structured interviews and self-report measures to assess the frequency of meals and snacks eaten, as well as binge eating and eating disorder features. Overall, those who consumed more frequent meals, particularly breakfast, and snacks, weighed less. Breakfast, which was eaten on a daily basis by less than half of participants (n=74; 43%), was the least frequently eaten meal of the day. Participants (n=56; 32%) who ate three meals per day weighed significantly less, and had significantly fewer binges, than participants (n=117; 68%) who did not regularly eat three meals per day. Thus, eating more frequently, having breakfast and consuming three meals every day, have potentially important clinical applications for the treatment of BED given that the effectiveness of specific interventions within treatments for BED are unknown, and that weight loss outcome for BED has been poor.     

Explaining neurocognitive aging: is one factor enough?

As an introduction to the special issue on neurocognitive factors underlying age effects, we discuss a number of recent developments in the literature on aging. The classic distinction between generalized and process-specific cognitive changes with old age has reappeared in the distinctions between the frontal lobe hypothesis and more differentiated views of neurocognitive aging. We argue that neurological decay in the frontal cortex has important implications for cognitive control, but that the frontal lobe hypothesis does not capture the plethora of changes that characterize aging and incorrectly suggests a unitary effect.     

A randomized controlled trial on the long-term effects of a 1-month behavioral weight control program assisted by computer tailored advice

OBJECTIVES: To examine the long-term effects of a new behavioral weight control program (Kenkou-tatsujin, KT program). The program consisted of twice-interactive letter communications including computer-tailored personal advice on treatment needs and behavioral modification. DESIGN: A randomized controlled trial comparing Group KM: KT program with 6-month weight and targeted behavior's self-monitoring, Group K: KT program only, Group BM: an untailored self-help booklet with 7-month self-monitoring of weight and walking, and Group B: the self-help booklet only. PARTICIPANTS: Two hundreds and five overweight Japanese females were recruited via a local newspaper. MEASUREMENTS: Weight loss (body weight, BMI, reduction quotient, etc.) and behavioral changes (daily eating, exercise and sleeping habits). FINDINGS: A significant weight loss was observed in all groups. At 1 month, Groups KM and K were superior, but at 7 months, the mean weight loss was significantly more in Group KM than the other 3 groups. At 7 months, 8 dietary habits and 4 physical activities were improved in all subjects. Habitual improvement was related to the weight loss in Groups KM and K at 1 month.     

Happiness,eudaimonia, and other holy grails: What can job loss teach us about ‘One-size-fits-all’ theories of well-being?

Abstract

Positive psychology has made significant advances in our understanding of well-being, yet agreement about the definition and nature of well-being remains elusive. This study explores the experience of well-being from a bottom-up, naturalistic point of view and compares these inductive notions with existing a priori theories. Using a qualitative-focused case study methodology, this paper explores how everyday people describe well-being in the context of job loss among a sample of 20 workers from the Ottawa, Canada technology sector. Findings support integrated conceptualizations of hedonia and eudaimonia while also potentially identifying new notions of well-being. Identified themes include (a) life evaluation, (b) transitory experiencing, (c) growth and grounding, (d) environmental mastery/stability, (e) mental ill-being/ill-health, and (f) motivational mindsets/conditions. This study shows well-being to be a rich, pluralistic construct which includes the non-dualistic notions of both subjectivity and objectivity as well as encompassing notions related to the ‘what’ and ‘how’ of well-being.