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991.
Delayed matching to complex, two-picture samples (e.g., cat-dog) may be improved when the samples occasion differential verbal behavior. In Experiment 1, individuals with mental retardation matched picture comparisons to identical single-picture samples or to two-picture samples, one of which was identical to a comparison. Accuracy scores were typically high on single-picture trials under both simultaneous and delayed matching conditions. Scores on two-picture trials were also high during the simultaneous condition but were lower during the delay condition. However, scores improved on delayed two-picture trials when each of the sample pictures was named aloud before comparison responding. Experiment 2 replicated these results with preschoolers with typical development and a youth with mental retardation. Sample naming also improved the preschoolers' matching when the samples were pairs of spoken names and the correct comparison picture matched one of the names. Collectively, the participants could produce the verbal behavior that might have improved performance, but typically did not do so unless the procedure required it. The success of the naming intervention recommends it for improving the observing and remembering of multiple elements of complex instructional stimuli.  相似文献   
992.
What response times tell of children's behavior on the balance scale task   总被引:4,自引:0,他引:4  
Analysis of accuracy of responses to balance scale problems gives a global idea of the cognitive processes that underlie problem-solving behavior on this task. We show that response times (RTs) provide additional detailed information about the kind and duration of these processes. We derive predictions about the RTs from Siegler's (1981) model for the balance scale task, including the counterintuitive prediction that young adults are slower than children in solving particular balance scale problems. The predictions were tested in a study in which 191 6- to 22-year-old participants were presented with a computerized balance scale task. RTs were analyzed with regression models. In addition to qualitative differences between items, we also modeled quantitative differences between items in the regression models. Analyses supported the predictions and provided additional knowledge on the rules. Rule II was reformulated as a rule that always involves the encoding, but not always the correct application of the distance cue. RTs provided evidence for the use of a buggy-rule and not an addition-rule. Finally, a relation between rule inconsistency and increased RT was found.  相似文献   
993.
Recently, it has been recognized that the commonly used linear structural equation model is inadequate to deal with some complicated substantive theory. A new nonlinear structural equation model with fixed covariates is proposed in this article. A procedure, which utilizes the powerful path sampling for computing the Bayes factor, is developed for model comparison. In the implementation, the required random observations are simulated via a hybrid algorithm that combines the Gibbs sampler and the Metropolis-Hastings algorithm. It is shown that the proposed procedure is efficient and flexible; and it produces Bayesian estimates of the parameters, latent variables, and their highest posterior density intervals as by-products. Empirical performances of the proposed procedure such as sensitivity to prior inputs are illustrated by a simulation study and a real example.This research is fully supported by a grant from the Research Grant Council of the Hong Kong Special Administrative Region, China (Project No. CUHK 4346/01H). The authors are thankful to the Editor, the Associate Editor, and anonymous reviewers for valuable comments which improve the paper significantly, and grateful to ICPSR and the relevant funding agency for allowing use of the data in the example. The assistance of Michael K.H. Leung and Esther L.S. Tam is gratefully acknowledged.  相似文献   
994.
The relation between mother–infant coordinated interpersonal timing, an automated microanalytic measure of dyadic vocal coordination, and maternal sensitivity was explored. Thirty-five mothers and their developmentally normal 4-month-old infants were audio-recorded during a 20-min laboratory vocal interaction session, that was later analyzed for degree of vocal coordination. Maternal Sensitivity ratings (Ainsworth & Bell, 1969) were based on a video-taped 45-min unstructured laboratory interaction period. A significant curvilinear relation between the degree to which mother coordinated her noninterruptive co-occurring speech to that of her infant was found and revealed that mothers highest in sensitivity were characterized by moderate levels of coordination. Examining mother-infant interaction at the specific behavioral level, while incorporating tests of nonlinear trends, may provide important information about the nature of sensitive parenting.  相似文献   
995.
This study evaluates a measurement model for Attention Deficit/Hyperactivity Disorder (ADHD). The DSM-IV divides 18 symptoms into two groups, inattentive and hyperactive/impulsive. Elementary school teachers rated 21,161 children in 4 locations: Spain, Germany, urban US, and suburban US. Confirmatory factor analysis suggested that the 2-factor model (inattention, hyperactivity/impulsivity) shows the best fit. A third factor, impulsivity, was too slight to stand-alone. Children with academic performance problems were distinguished by inattention, but children with behavior problems typically had elevations in inattention, hyperactivity, and impulsivity. Between-site differences were statistically significant, but so small that we conclude that same measurement model fits all 4 samples in 2 continents.  相似文献   
996.
The papers in this special issue of Clinical Child and Family Psychology Review provided an overview of what is known about children's exposure to domestic violence, and include indications of gaps in extant research. These gaps and research needs are summarized in this conclusion. Specifically, there is need for further research in several broad areas: definition and measurement of children's exposure to domestic violence; development of research methods and statistical designs that provide detailed information and provide for evidence of intervention effectiveness; impact of domestic violence on parenting and family functioning; the role of child factors and exposure to violence factors in predicting developmental risk and resilience; medical and health consequences of exposure to violence; and the nature of child-system interaction in response to domestic violence. Research needs in these areas are discussed in greater detail, and specific questions are raised for further development.  相似文献   
997.
Three definitional issues regarding children exposed to domestic violence are examined. First, the multiple ways in which a child can be exposed to violence is discussed. A taxonomy of 10 types of exposure is proposed. Nine key characteristics of domestic violence, as they relate to children and children's exposure, are then outlined. The third issue addressed concerns why children who are exposed to domestic violence can be considered victims of child maltreatment. These children, by nature of their experience in the home, are psychologically maltreated and are also at high risk for physical abuse and some risk for sexual abuse. Empirical questions concerning these definitions and taxonomies and their interrelations are discussed.  相似文献   
998.
Introduction     
This issue of Clinical Child and Family Psychology Review, Children Exposed to Domestic Violence: Current Status and Research Directions, addresses the current status of our knowledge as well as critical research needs in the area of children exposed to domestic violence. Although much has been learned in recent years about children exposed to violence, significant research gaps remain, the identification of which may help to build a more complete and rigorous science base in this area. This journal issue represents the distillation of a 3-day workshop on children exposed to violence, held in July of 2002, that identified what is known about children exposed to violence and what this information tells us about future research directions. Although many federal agencies have supported some research in this area, there is a need for more targeted attention on the topic, particularly with regard to measurement, sampling, and interventions/services. The papers in this issue were selected with these themes in mind. Although no single issue could cover the entire field, we intend to offer a representative sample of where we are and where we need to go with the hope of stimulating additional thought, collaboration, and research in this important area.  相似文献   
999.
In this editorial contribution, two issues relevant to the question, what should be at the top of the research agenda for ethics and technology, are identified and discussed. Firstly: can, and do, engineers make a difference to the degree to which technology leads to morally desirable outcomes? What role does professional autonomy play here, and what are its limits? And secondly, what should be the scope of engineers' responsibility; that is to say, on which issues are they, as engineers, morally obliged to reflect? The research agendas proposed by the authors contributing to this special section, implicitly, give different answers to these questions. We suggest that an explicit discussion of these issues would greatly help in constructing a common research agenda.  相似文献   
1000.
A multiple chained schedule was used to compare the relative resistance to change of variable and fixed four-peck response sequences in pigeons. In one terminal link, a response sequence produced food only if it occurred infrequently relative to 15 other response sequences (vary). In the other terminal link, a single response sequence produced food (repeat). Identical variable-interval schedules operated in the initial links. During baseline, lower response rates generally occurred in the vary initial link, and similar response and reinforcement rates occurred in each terminal link. Resistance of responding to prefeeding and three rates of response-independent food delivered during the intercomponent intervals then was compared between components. During each disruption condition, initial- and terminal-link response rates generally were more resistant in the vary component than in the repeat component. During the response-independent food conditions, terminal-link response rates were more resistant than initial-link response rates in each component, but this did not occur during prefeeding. Variation (in vary) and repetition (in repeat) both decreased during the response-independent food conditions in the respective components, but with relatively greater disruption in repeat. These results extend earlier findings demonstrating that operant variation is more resistant to disruption than is operant repetition and suggest that theories of response strength, such as behavioral momentum theory, must consider factors other than reinforcement rate. The implications of the results for understanding operant response classes are discussed.  相似文献   
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