A Limited Information Estimator for Dynamic Factor Models

Structural equation modeling (SEM) is an increasingly popular method for examining multivariate time series data. As in cross-sectional data analysis, structural misspecification of time series models is inevitable, and further complicated by the fact that errors occur in both the time series and measurement components of the model. In this article, we introduce a new limited information estimator and local fit diagnostic for dynamic factor models within the SEM framework. We demonstrate the implementation of this estimator and examine its performance under both correct and incorrect model specifications via a small simulation study. The estimates from this estimator are compared to those from the most common system-wide estimators and are found to be more robust to the structural misspecifications considered.     

Adapting the cognitive interview to enhance long-term (35 years) recall of physical activities

The cognitive interview (CI) was modified for use in an epidemiological study in which respondents were asked to recall their daily physical activities from the distant past (35 years ago). In comparison to a traditional epidemiological interview, the CI elicited many more responses and also more precise responses. Several practical costs, however, were incurred by the CI: additional time to train interviewers and to conduct interviews and difficulties in coding the responses. The costs and benefits of conducting the CI are addressed, along with conceptual and methodological challenges. The article ends with an existential question: Is the CI a singular technique if it can be modified so radically for different settings?     

Resolving disease management problems in European-American and Latino couples with type 2 diabetes: the effects of ethnicity and patient gender

The management of type 2 diabetes requires major life style changes. How patients and family members resolve disagreements about disease management affects how well the disease is managed over time. Our goal was to identify differences in how couples resolved disagreements about diabetes management based on ethnicity and patient gender. We recruited 65 Latino and 110 European-American (EA) couples in which one spouse had type 2 diabetes. Couples participated in a 10-minute videotaped, revealed differences interaction task that was evaluated with 7 reliable observer ratings: warm-engagement, hostility, avoidance, amount of conflict resolution, off-task behavior, patient dominance, and dialogue. A series of 2 x 2, Ethnicity x Sex ANOVAs indicated significant effects for Ethnicity and for the Ethnicity x Sex interaction, but not for Sex. Latino couples were rated as significantly more emotionally close, less avoidant, less hostile toward each other, and had less dominant patients than EA couples; however, Latino couples achieved significantly less problem resolution and were more frequently off-task than EA couples. These findings were qualified by patient gender. The findings highlight important differences     

Neural mechanisms of affective interference in schizotypy

Negatively valenced stimuli foster cognitive impairment in schizotypy and schizophrenia. To identify relevant brain mechanisms, the authors had 16 positive-schizotypy and 16 control participants perform an emotional Stroop task, judging the ink color of negative and neutral words during functional magnetic resonance imaging (fMRI) of regional brain activity. Schizotypy individuals showed increased right and decreased left activity in dorsolateral prefrontal cortex, indicating a deficit in maintenance of attentional set in the presence of negative emotional distractors. They also showed abnormal activity in ventral limbic areas, including decreased activity in nucleus accumbens and increased activity in hippocampus and amygdala, a circuit involved in the integration of cognitive and affective processes. These results indicate that aspects of emotion-cognition processes and the brain mechanisms that implement them are similar in schizotypy and schizophrenia.     

Multiple-object tracking is based on scene, not retinal, coordinates

This study tested whether multiple-object tracking-the ability to visually index objects on the basis of their spatiotemporal history-is scene based or image based. Initial experiments showed equivalent tracking accuracy for objects in 2-D and 3-D motion. Subsequent experiments manipulated the speeds of objects independent of the speed of the scene as a whole. Results showed that tracking accuracy was influenced by object speed but not by scene speed. This held true whether the scene underwent translation, zoom, rotation, or even combinations of all 3 motions. A final series of experiments interfered with observers' ability to see a coherent scene by moving objects at different speeds from one another and by distorting the perception of 3-D space. These reductions in scene coherence led to reduced tracking accuracy, confirming that tracking is accomplished using a scene-based, or allocentric, frame of reference.     

Deception research involving children: ethical practices and paradoxes

This commentary draws on the thoughtful contemplation and innovative procedures described in the special section articles as well as current professional codes and federal regulations to highlight ethical practices and paradoxes of deception research involving children. The discussion is organized around 4 key decision points for the conduct of responsible deception research involving children: (a) evaluating the scientific validity and social value of deception research within the context of alternative methodologies, (b) avoiding and minimizing experimental risk, (c) the use of child assent procedures as questionable ethical safeguards, and (d) debriefing as both remedy and risk.     

When development and learning decrease memory. Evidence against category-based induction in children

Inductive inference is crucial for learning: If one learns that a cat has a particular biological property, one could expand this knowledge to other cats. We argue that young children perform induction on the basis of similarity of compared entities, whereas adults may induce on the basis of category information. If different processes underlie induction at different points in development, young children and adults would form different memory traces during induction, and would subsequently have different memory accuracy. Experiment 1 demonstrates that after performing an induction task, 5-year-olds exhibit more accurate memory than adults. Experiment 2 indicates that after 5-year-olds are trained to perform induction in an adultlike manner, their memory accuracy drops to the level of adults. These results, indicating that sometimes 5-year-olds exhibit better memory than adults, support the claim that, unlike adults, young children perform similarity-based rather than category-based induction.     

Are dietary restraint scales valid measures of acute dietary restriction? Unobtrusive observational data suggest not

The finding that dietary restraint scales predict onset of bulimic pathology has been interpreted as suggesting that dieting causes this eating disturbance, despite the dearth of evidence that these scales are valid measures of dietary restriction. The authors conducted 4 studies that tested whether dietary restraint scales were inversely correlated with unobtrusively measured caloric intake. These studies, which varied in foods consumed, settings, and populations, indicated that common dietary restraint scales were largely uncorrelated with acute caloric intake. Results suggest that these scales are not valid measures of short-term dietary restriction and imply that it may be prudent to reinterpret findings from studies thai use these scales, including those that suggest dietary restraint is a risk factor for bulimic pathology.     

Enhancing the effects of extinction on attention-maintained behavior through noncontingent delivery of attention or stimuli identified via a competing stimulus assessment

Recent research has shown that the noncontingent delivery of competing stimuli can effectively reduce rates of destructive behavior maintained by social-positive reinforcement, even when the contingency for destructive behavior remains intact. It may be useful, therefore, to have a systematic means for predicting which reinforcers do and do not compete successfully with the reinforcer that is maintaining destructive behavior. In the present study, we conducted a brief competing stimulus assessment in which noncontingent access to a variety of tangible stimuli (one toy per trial) was superimposed on a fixed-ratio 1 schedule of attention for destructive behavior for individuals whose behavior was found to be reinforced by attention during a functional analysis. Tangible stimuli that resulted in the lowest rates of destructive behavior and highest percentages of engagement during the competing stimulus assessment were subsequently used in a noncontingent tangible items plus extinction treatment package and were compared to noncontingent attention plus extinction and extinction alone. Results indicated that both treatments resulted in greater reductions in the target behavior than did extinction alone and suggested that the competing stimulus assessment may be helpful in predicting stimuli that can enhance the effects of extinction when noncontingent attention is unavailable. DESCRIPTORS: Attention-maintained problem behavior, competing stimuli, extinction, functional analysis, noncontingent reinforcement     

Systematic application and removal of protective equipment in the assessment of multiple topographies of self-injury

We evaluated the effects of systematic application and removal of protective equipment on three topographies of self-injurious behavior (SIB) exhibited by a girl who had been diagnosed with autism. Results showed that when protective equipment was applied, SIB decreased to near-zero levels. In addition, withdrawal of protective equipment for specific topographies of SIB (by removing only the corresponding padding) increased rates of SIB only for that topography of SIB. Next, a functional analysis of hand SIB showed that protective equipment suppressed this behavior in all conditions and that the behavior was maintained by automatic reinforcement when padding was removed. Results are discussed in terms of sensory extinction as a possible mechanism responsible for response suppression.