Description:
Item response theory (IRT) based differential item functioning (DIF) was used to examine the construct and normative invariance of the DSM-IV oppositional defiant disorder (ODD) symptoms for ratings across Malaysian and Australian children, and Malaysian Malay and Malaysian Chinese children. To accomplish these goals, parents completed the Disruptive Behavior Rating Scale, which includes the eight DSM-IV ODD symptoms. Although the comparisons involving Malaysian and Australian children indicated DIF for five symptoms, only the symptom for “touchy” showed notable DIF. This was also the only symptom that showed DIF for the comparisons involving Malay and Chinese children. There were also minimal differences in the latent mean scores across Australian and Malaysian children and also Malay and Chinese children. These results indicate good support for the construct and normative invariance of the ODD symptoms for the samples compared.
Description:
Using any nonnegative function with a nonpositive derivative along trajectories to define a virtual output, the classic LaSalle invariance principle can be extended to switched nonlinear time-varying (NLTV) systems, by considering the weak observability associated with this output. The concept of weak observability reflects the information of the limiting behavior of state trajectories hidden in the zero locus of the output. In the context of switched NLTV systems, weak observability can be explored using the recently established framework of limiting zeroing-output solutions. Adding to this, a new approach to show uniform global attractivity of a closed set (without assuming uniform Lyapunov stability or dwell-time conditions) is proposed. A further extension of the generalized LaSalle invariance principle allows the consideration of cascaded switched NLTV systems, which is used to characterize how consensus in a leaderless swarm of nonholonomic robots allowing for switching communication topologies may be established.
Description:
Objective: This study used the mean and covariance structures analysis approach to examine the equality or invariance of ratings of the 18 ADHD symptoms. Method: 783 Australian and 928 Malaysian parents provided ratings for an ADHD rating scale. Invariance was tested across these groups (Comparison 1), and North European Australian (n = 623) and Malay Malaysian (n = 571, Comparison 2) groups. Results: Results indicate support for form and item factor loading invariance; more than half the total number of symptoms showed item intercept invariance, and 14 symptoms showed invariance for error variances. There was invariance for both the factor variances and the covariance, and the latent mean scores for hyperactivity/impulsivity. For inattention latent scores, the Malaysian (Comparison 1) and Malay Malaysian (Comparison 2) groups had higher scores. Conclusion: These results indicate fairly good support for invariance for parent ratings of the ADHD symptoms across the groups compared. (J. of Att. Diss. 2009; 12(5) 422-433)
Description:
DSM-IV conceptualizes Attention Deficit/Hyperactivity Disorder (ADHD) in terms of two symptoms groups, namely inattention (IA; 9 symptoms) and hyperactivity/impulsivity (HI; 9 symptoms). The current study used confronatory factor analysis to examine the invariance of parent and teacher ratings of the ADHD symptoms for an Australian community sample of primary school children. To achieve this goal, parents and teachers of 1475 children completed a DSM-IV based ADHD rating scale. The results indicated support for configural invariance, and for full metric, scalar and error variances invariance. Findings also indicated invariance fro IA and HI latent variances, covariance between these factors, and their latent mean scores. These findings extend existing data in this area. The clinical and theoretical implication of the findings are discussed.
The spiritual well-being questionnaire : Testing for model applicability, measurement and structural equivalencies, and latent mean differences across gender