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141.
This study examined the persistence of attention-deficit/hyperactivity disorder (ADHD) into young adulthood using hyperactive (N = 147) and community control (N = 71) children evaluated at ages 19-25 years. ADHD was rare in both groups (5% vs. 0%) based on self-report but was substantially higher using parent reports (46% vs. 1.4%). Using a developmentally referenced criterion (+2 SD), prevalence remained low for self-reports (12% vs. 10%) but rose further for parent reports (66% vs. 8%). Parent reports were more strongly associated with major life activities than were self-reports. Recollections of childhood ADHD showed moderate correlations with actual parent ratings collected in childd hood, which suggests some validity for such recollections. The authors conclude that previous follow-up studies that relied on self-reports might have substantially underestimated the persistence of ADHD into adulthood.  相似文献   
142.
Although self-enhancement is linked to psychological benefits, it is also associated with personal and interpersonal liabilities (e.g., excessive risk taking, social exclusion). Hence, structuring social situations that prompt people to keep their self-enhancing beliefs in check can confer personal and interpersonal advantages. The authors examined whether accountability can serve this purpose. Accountability was defined as the expectation to explain, justify, and defend one's self-evaluations (grades on an essay) to another person ("audience"). Experiment 1 showed that accountability curtails self-enhancement. Experiment 2 ruled out audience concreteness and status as explanations for this effect. Experiment 3 demonstrated that accountability-induced self-enhancement reduction is due to identifiability. Experiment 4 documented that identifiability decreases self-enhancement because of evaluation expectancy and an accompanying focus on one's weaknesses.  相似文献   
143.
The power function exponent for loudness is traditionally determined by means of a process of magnitude estimation. It is demonstrated in this paper that the exponent can also be obtained by using the procedure of absolute identification of sound intensity. It has been shown that subjects' responses to tones of a given intensity are distributed in a normal distribution whose variance depends on the range, R, over which the tones are distributed. By means of a standard statistical transformation, the normal density in log space is converted to the corresponding probability density in linear space. The power function exponent can then be obtained directly from the linear probability density. We also suggest that there is a direct relationship between the information calculated from experiments on absolute identification of sound intensity and the neurophysiological, poststimulus histogram measured in a nerve fiber in the auditory nerve.  相似文献   
144.
The Fisher-Pitman permutation test is shown to possess significant advantages over conventional alternatives when analyzing differences among independent samples with unequal variances.  相似文献   
145.
In comparison to younger adults, older adults demonstrate deficiencies in cognitive and linguistic abilities. Such cognitive factors that decline with age include working memory capacity and inhibitory abilities. The purpose of the present investigation was to measure differences in time course processing of inference revision abilities, as well as working memory, as they exist relative to adult age differences. Fifteen neurologically intact older adults and 15 younger adults participated in this study. A cross-modal lexical priming paradigm was chosen as the measure of the inference revision task; the listening span task of Tompkins, Bloise, Timko, and Baumgaertner (1994) was selected as the measure of working memory. Both groups demonstrated normal priming effects. No age-related differences were found on the working memory measure. Age-related differences did emerge on inferencing abilities. A significant correlation emerged between the older group's performance on comprehending inference revisions and their working memory capacity. Generally, inhibitory abilities and working memory capacity appeared to adversely affect older participant's performance.  相似文献   
146.
A classical question for memory researchers is whether memories vary in an all-or-nothing, discrete manner (e.g., stored vs. not stored, recalled vs. not recalled), or whether they vary along a continuous dimension (e.g., strength, similarity, or familiarity). For yes-no classification tasks, continuous- and discrete-state models predict nonlinear and linear receiver operating characteristics (ROCs), respectively (D. M. Green & J. A. Swets, 1966; N. A. Macmillan & C. D. Creelman, 1991). Recently, several authors have assumed that these predictions are generalizable to confidence ratings tasks (J. Qin, C. L. Raye, M. K. Johnson, & K. J. Mitchell, 2001; S. D. Slotnick, S. A. Klein, C. S. Dodson, & A. P. Shimamura, 2000, and A. P. Yonelinas, 1999). This assumption is shown to be unwarranted by showing that discrete-state ratings models predict both linear and nonlinear ROCs. The critical factor determining the form of the discrete-state ROC is the response strategy adopted by the classifier.  相似文献   
147.
Forster KI 《Memory & cognition》2000,28(7):1109-1115
Word recognition experiments that involve comparisons between two different matched sets of words allow for possible experimenter bias if there are many equally well-matched pairs to choose from. The possible extent of this bias depends on the experimenter's intuitive knowledge of the likely difficulty of individual items. This is assessed by asking a number of experimenters to decide which of two frequency-matched words would produce the fastest reaction time in a lexical decision experiment, and then comparing their predictions with actual data. All experimenters demonstrated substantial above-chance accuracy, which was unrelated to the amount of experience they had in the field. It was concluded that the experimenters could potentially produce spurious effect sizes ranging from 16 to 38 msec.  相似文献   
148.
149.
This investigation compared the likelihood of insomnia and insomnia-related health consequences among individuals of different socioeconomic status. A random-digit dialing procedure was used to recruit at least 50 men and 50 women in each age decade from 20 to 80+ years old. Participants completed 2 weeks of sleep diaries as well as questionnaires related to fatigue, sleepiness, and psychological distress. Socioeconomic status was measured by education status assessed at 3 different levels: individual, household, and community. Results indicated that individuals of lower individual and household education were significantly more likely to experience insomnia even after researchers accounted for ethnicity, gender, and age. Additionally, individuals with fewer years of education, particularly those who had dropped out of high school, experienced greater subjective impairment because of their insomnia.  相似文献   
150.
This study examined the effect of school-based kindergarten transition policies and practices on child outcomes. The authors followed 17,212 children from 992 schools in the Early Childhood Longitudinal Study-Kindergarten sample (ECLS-K) across the kindergarten school year. Hierarchical linear modeling revealed that the number of school-based transition practices in the fall of kindergarten was associated with more positive academic achievement scores at the end of kindergarten, even controlling for family socioeconomic status (SES) and other demographic factors. This effect was stronger for low- and middle-SES children than high-SES children. For low-SES children, 7 transition practices were associated with a .21 standard deviation increase in predicted achievement scores beyond 0 practices. The effect of transition practices was partially mediated by an intervening effect on parent-initiated involvement in school during the kindergarten year. The findings support education policies to target kindergarten transition efforts to increase parent involvement in low-SES families.  相似文献   
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