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231.
Exploratory and confirmatory factor analyses of the pervasive developmental disorders rating scale for young children with autistic disorder 总被引:1,自引:0,他引:1
In this study, the authors examined the construct validity of the Pervasive Developmental Disorder Rating Scale (PDDRS; R. C. Eaves, 1993), which is a screening instrument used to identify individuals with autistic disorder and other pervasive developmental disorders. The PDDRS is purported to measure 3 factors--arousal, affect, and cognition-that collectively make up the construct of autism. Using scores from 199 children (aged 1-6 years) diagnosed with autistic disorder, the authors submitted data to exploratory and confirmatory factor analyses. In the 1st series of analyses, the authors analyzed a user-specified 3-factor solution using principal axis factor analysis with a promax rotation to evaluate the assertion of a correlated 3-factor structure. Next, the authors analyzed 1-factor and 2-factor solutions to determine if they provided a better factor structure for the data. In the 2nd series, the authors conducted confirmatory factor analyses, which compared the theorized hierarchical 2nd-order factor model with 5 plausible competing models. The results of the exploratory analyses supported the 3-factor solution. With the confirmatory analyses, the 2nd-order factor model provided the best fit for the data. The exploratory and confirmatory analyses supported the theoretical assumptions undergirding the development of the PDDRS. The authors discuss theoretical implications, practical implications, and areas for further research. 相似文献
232.
In this study, the authors examined the stability of Minnesota Multiphasic Personality Inventory--2 (J. N. Butcher, W. G. Dahlstrom, J. R. Graham, A. Tellegen, & B. Kaemmer, 1989) code types in a sample of 94 injured workers with a mean test-retest interval of 21.3 months (SD = 14.1). Congruence rates for undefined code types were 34% for high-point codes, 22% for 2-point codes, and 22% for 3-point codes. The data provide tentative evidence suggesting that defined code types are more stable than undefined code types. Cohen's kappa, a statistic that controls for chance agreement, was calculated for each clinical scale for both 2-point and 3-point code types. Only 2 of the 20 kappa coefficients were not significant at the p = .05 level. 相似文献
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235.
The Rev. Ronald E. Whittall 《Pastoral Psychology》1969,20(10):50-52
236.
Taylor TG Galuska CM Banna K Yahyavi-Firouz-abadi N See RE 《Journal of the experimental analysis of behavior》2010,93(2):261-267
The effectiveness of a fixed‐ratio (FR) escalation procedure, developed by Pinkston and Branch (2004) and based on interresponse times (IRTs), was assessed during lever‐press acquisition. Forty‐nine experimentally naïve adult male Long Evans rats were deprived of food for 24 hr prior to an extended acquisition session. Before the start of the session, three food pellets were placed in the magazine. Otherwise, no magazine training, shaping, nor autoshaping procedure was employed. The first 20 presses each resulted in the delivery of a 45‐mg food pellet. Then, the FR increased (2, 4, 8, 11, 16, 20, 25, 30) when each IRT in the ratio was less than 2 s during three consecutive ratios. Sessions lasted 13 hr or until 500 pellets were earned. On average, rats reached a terminal ratio of 11 (mean) or 16 (median) during the first session. Seven rats reached the maximum value of FR 30 and only one rat did not acquire the response. In most rats, a break‐and‐run pattern of responding characteristic of FR schedules began to develop in this acquisition session. Subsequently, the ratio‐escalation procedure continued during daily 2‐hr sessions. In these sessions, the starting ratio requirement was set at the terminal ratio reached in the previous session. Using this procedure, over half (26) of the rats reached the FR 30 requirement by the fourth session. These data demonstrate that a ratio‐escalation procedure based on IRTs provides a time‐efficient way of establishing ratio responding. 相似文献
237.
We studied the development of creative cognition in children ranging from nursery school to Grade 6 (4–12 yr old, N = 511), performing a problem generation task. The task involved inventing a novel item for a classical problem solving task they had completed beforehand: the Raven Progressive Matrices (RPM). This task and the generating task both comprise matrixes of components, to which a set of transformational relations are applied; only in the first case these are inferred to solve a puzzle, but in the second they are invented to create one. We analyzed the matrixes invented in the generation task and compared them to those of the original solving task. We observed that (a) both in solving and generation, the ability to combine more than 1 relation increased with grade level, (b) within all 8 grades, except Grades 3 and 6, performance was uncorrelated between both tasks, (c) relations that were applied in the generation task often did feature in the solving task, and (d) relations occurring in both tasks were applied with different frequencies. Overall, we conclude that standard problem solving ability is not a precondition for creative reasoning and that the comprehension of relations between components featured in solving task differs from that applied in generation. 相似文献
238.
Daniel J. O’Rourke Ronald E. Smith Frank L. Smoll Sean P. Cumming 《Journal of Applied Sport Psychology》2013,25(4):398-412
We assessed the role of parental behaviors on sport performance anxiety. Measures of trait anxiety, parental pressure, and parent-initiated motivational climate were administered to youth swimmers throughout the season. High parental pressure within either a low mastery or a high ego motivational climate was associated with the highest levels of anxiety at all time points. An early-season, high-pressure/low-mastery combination was also associated with relative increases in anxiety over the season, whereas high pressure within a high mastery climate was associated with relative decreases. Results indicate that parental pressure can have differential effects depending upon motivational climate. 相似文献
239.
The authors collected information from caregivers, trained observers, and parents to investigate quality elements in child-care programs designed for young children in center-based settings. Participants were 75 parents of children aged 15 to 36 months and their caregivers from 13 child-care centers in a southeastern state. Observers collected indicators of program quality and process and structural quality indicators, including adult-child ratio, group size, use of planned activities, use of child-designated space, housekeeping activities, and caregiver-child interactions. Participants responded to questions regarding their child-rearing beliefs, social support networks, perceived stress levels, and demographic characteristics. The best predictors of higher quality care and sensitive caregiver-child interaction in centers were specialized caregiver training, higher adult-child ratios, use of planned activities, and less perceived stress by caregivers. Implications of these findings are discussed. 相似文献
240.
Seventy-two first, second and third grade boys and girls were administered seriation problems involving different combinations of shape and color variation. Success rates and latency scores were influenced by shape variation, but not by color variation or grade level. The failure to obtain predicted interactions between the effects of grade level and stimulus variation was attributed to the clarity of the relevant stimulus dimension. 相似文献