Estimation for structural equation models with missing data

A direct method in handling incomplete data in general covariance structural models is investigated. Asymptotic statistical properties of the generalized least squares method are developed. It is shown that this approach has very close relationships with the maximum likelihood approach. Iterative procedures for obtaining the generalized least squares estimates, the maximum likelihood estimates, as well as their standard error estimates are derived. Computer programs for the confirmatory factor analysis model are implemented. A longitudinal type data set is used as an example to illustrate the results.This research was supported in part by Research Grant DAD1070 from the U.S. Public Health Service. The author is indebted to anonymous reviewers for some very valuable suggestions. Computer funding is provided by the Computer Services Centre, The Chinese University of Hong Kong.     

A post hoc correction procedure for systematic errors in time-sampling duration estimates

Numerous previous studies have shown that partial-interval sampling in direct observation systematically overestimates duration and underestimates frequency. Whole-interval sampling systematically underestimates both duration and frequency. This paper presents a post hoc method through which the systematic errors in duration estimates in partial-interval sampling and whole-interval sampling can be minimized.     

Behavioral assessment of methylphenidate in a child with frontal lobe damage

The assessment and management of inattentive, hyperactive, and impulsive behavior in a 6-year-old girl who experienced frontal lobe damage are described. A multimodel approach combining medical, educational, and behavioral techniques to assess hyperactive behavior, optimal medication level, and medication and psychotherapeutic effectiveness is described. The results of the study suggest that in similar cases, children and adolescents manifesting these behaviors should be given a trial of stimulant medication in a controlled environment to assess if such therapy is indicated. Additional support is given for the increasing need for detanté and cooperation with health-care professionals.     

Social and solipsistic observer training: Effects on agreement with a criterion

The need to train accurate, not necessarily agreeing, observers is discussed. Intraobserver consistency as an intermediate criterion in such training is proposed and contrasted with the more familiar criterion of interobserver agreement. Videotaped observations of social interactions between handicapped and nonhandicapped preschoolers provided the medium for examining the criterion agreement of four observers trained against each type of standard. Observers generally failed to show high levels of criterion agreement whether trained to a within- or to a between-observer agreement standard. The results varied somewhat with the frequency of behaviors, however. Correlations between interobserver agreement and intraobserver consistency were variable but somewhat higher when interobserver agreement was the training criterion than when intraobserver consistency was the criterion. Correlations between interobserver agreement and criterion agreement ranged from — .16 to .89 during interobserver agreement training. Correlations between intraobserver consistency and criterion agreement ranged from — .23 to .99 during intraobserver consistency training.     

Behavior regulation and learned performance: Some misapprehensions and disagreements

The behavior-regulation approach to learned performance has been the subject of misapprehension and disagreement concerning: (1) the nature and importance of behavior regulation, (2) the definition and role of behavioral set-points, (3) the relation of optimal schedule performance to behavioral set-points, and (4) the question of whether deviations from total responding or from response patterns are the primary determinant of molar responding under schedule constraint. After clarifying the nature and role of behavior regulation and set-points, this paper shows that the data used to question optimal schedule performance (Allison, 1981a) actually strongly support the general behavior-regulation approach. These data also indicate a role for response-pattern set-points in determining schedule behavior, but contradict the hypothesis that deviations from response-pattern characteristics are the primary determinant of molar schedule effects.     

CONTINGENT REINFORCEMENT FOR CARBON MONOXIDE REDUCTION: WITHIN-SUBJECT EFFECTS OF PAY AMOUNT

The relationship between reinforcer amount and daytime smoking reduction in smokers offered money for reduced afternoon breath carbon monoxide (CO) levels was examined. Twenty-three hired regular smokers with average baseline CO levels of about 30 ppm were exposed in random order to five sliding scale payment schedules that changed daily or weekly. Money was available for afternoon CO readings between 0 and 21 ppm with pay amount inversely related to the absolute CO reading obtained. Maximum pay amount for readings below 7 ppm varied among $0, $1.50, $3, $6, and $12 per day. Contingent reinforcement promoted CO and daytime cigarette reduction within individuals with the amount of behavior change related to the amount of payment available. Average CO levels decreased from 30 to 15 ppm as a function of pay amount whereas self-reported daytime cigarettes decreased from 12 to 5 per day. Average minutes of cigarette abstinence prior to the afternoon study contact increased from 62 to 319 minutes as a function of pay amount, whereas the percentage of available money earned increased from 22% to 48%. Nontargeted evening cigarette use also decreased during periods of daytime smoking reduction. The orderly effects of this contingent reinforcement intervention on daytime smoking of regular smoker volunteers suggest that this is a sensitive model for continued evaluation of factors that influence smoking reduction and cessation.     

THE EFFECT OF INFORMATIONAL FEEDBACK ON FOOD INTAKE OF ADULT BURN PATIENTS

The effect of informational feedback on the protein and caloric consumption of burn patients was investigated using a multiple-baseline across subjects. The patients were four severely burned adult males who failed to consume sufficient foods to achieve prescribed levels of protein or kilocalories via standard burn unit procedures during recovery. Feedback consisted of informing patients of (a) their prescribed levels of protein and kilocalories, (b) the protein and kilocalorie content of hospital foods and beverages, and (c) their actual intake of protein and kilocalories. Following the provision of feedback, there was an increase in protein and kilocalorie intakes and in the number of days during which prescribed levels for protein and kilocalories were achieved. These results suggest that the informational feedback was effective for improving the oral caloric intake of burn patients.     

A general structural equation model with dichotomous,ordered categorical,and continuous latent variable indicators

A structural equation model is proposed with a generalized measurement part, allowing for dichotomous and ordered categorical variables (indicators) in addition to continuous ones. A computationally feasible three-stage estimator is proposed for any combination of observed variable types. This approach provides large-sample chi-square tests of fit and standard errors of estimates for situations not previously covered. Two multiple-indicator modeling examples are given. One is a simultaneous analysis of two groups with a structural equation model underlying skewed Likert variables. The second is a longitudinal model with a structural model for multivariate probit regressions.This research was supported by Grant No. 81-IJ-CX-0015 from the National Institute of Justice, by Grant No. DA 01070 from the U.S. Public Health Service, and by Grant No. SES-8312583 from the National Science Foundation. I thank Julie Honig for drawing the figures. Requests for reprints should be sent to Bengt Muthén, Graduate School of Education, University of California, Los Angeles, California 90024.     

Correspondence between resident- and staff-report on the QABF: Do justice-involved youth agree with residential staff?

Residents in juvenile residential treatment facilities (JRTFs) often display various emotional, behavioral, and educational needs. Researchers have recently developed behavioral interventions to increase residents' appropriate behavior such as cooperation with facility staff instructions, accepting feedback from facility staff, and tolerating unpleasant events. However, there is not a generally accepted tool for assessing the operant function of residents' problem behavior in JRTFs. For various logistical reasons, indirect functional assessments may be more appropriate in a JRTF than manipulating either antecedent or consequent events. This study obtained scores on the Questions About Behavior Function (QABF) assessment for 17 residents from two dormitory staff members for each resident. To increase the number of respondents, each resident completed a QABF for their own behavior. Results revealed moderate to high correspondence (i.e., agreement) for highest and lowest potential operant function of problem behavior between combinations of JRTF staff and residents. These preliminary findings suggest additional research with the QABF in JRTFs is warranted.     

Modified Comprehensive Behavioral Intervention for Tics: Treating Children With Tic Disorders,Co-Occurring ADHD,and Psychosocial Impairment

Our objective was to evaluate the feasibility and acceptability, and preliminary efficacy of a modified comprehensive behavioral intervention for tics (MCBIT) therapy for youth with chronic tic disorders (CTDs), co-occurring attention-deficit hyperactivity disorder (ADHD), and associated psychosocial impairment. Seventeen youth ages 10–17 with CTD and co-occurring ADHD were randomly assigned to the MCBIT group (n = 9) or to a control group where they received traditional comprehensive behavioral intervention for tics (CBIT) therapy (n = 8). Both groups received ten 55-minute weekly treatment sessions, and two 55-minute biweekly relapse prevention sessions. Sixteen of the 17 participants completed the study, and acceptability ratings in both treatment groups were high with no significant differences in expectation of improvement. The MCBIT and CBIT groups in combination showed significant improvement in tic severity, ADHD symptom severity, and tic-related impairment. Group differences were not significant. The results indicate that MCBIT treatment is feasible and acceptable for youth with CTD and ADHD, and is similarly well tolerated relative to traditional CBIT. Results were not sufficiently superior to recommend MCBIT over CBIT for this population. However, given the demonstrated benefit of behavioral treatments that target co-occurring conditions concurrently, continuing to examine novel behavioral approaches that can target tics and related conditions simultaneously and successfully is recommended.