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71.
The monetary choice questionnaire (MCQ) and similar computer tasks ask preference questions in order to ascertain indifference, the perceived equivalence of immediate versus larger delayed rewards. Indifference data are then fitted with a hyperbolic function, summarizing the decline in perceived value with delay time. We present a fitting method that estimates the hyperbolic parameterk directly from survey responses. Binary preferences are modeled as a function of time (X2) and a transformed reward ratio (X 1), yielding logistic regression coefficients β2 and β1. The hyperbolic parameter emerges ask = β21, where the logistic predictedp = .5 (the definition of indifference). The MCQ was administered to 1,073 adolescents and was scored using both standard and logistic methods. The means for ln(k) were similar (standard, −4.53; logistic, −4.51), and the results were highly correlated (ρ = .973). Simulated MCQ data showed thatk was unbiased, except where β1 ≥ −1, indicating a vague survey response. Jackknife standard errors provided excellent coverage.  相似文献   
72.
The objective was to evaluate the validity of sluggish cognitive tempo (SCT) and ADHD-inattention (IN) symptoms in children from Nepal. Teachers rated SCT, ADHD-IN, ADHD-hyperactivity/impulsivity (HI), oppositional defiant disorder (ODD), anxiety, depression, academic impairment, social impairment, and peer rejection dimensions in 366 children (50 % girls) in first through sixth grades (M age?=?9.35, SD age?=?1.96) on two separate occasions separated by 4-weeks. Seven of the eight SCT symptoms and all nine ADHD-IN symptoms showed convergent validity (substantial loadings on their respective factors) and discriminant validity (higher loadings on their respective factor than the alternative factor) at both time-points. Across all three separate analyses (assessment 1, assessment 2, and from assessment 1 to assessment 2), higher SCT scores were associated with lower ADHD-HI scores and higher depression, academic impairment, and social impairment scores after controlling for ADHD-IN while higher ADHD-IN scores were associated with higher ADHD-HI, ODD, academic impairment, and peer rejection scores after controlling for SCT. Also, as hypothesized, SCT scores were not related to ODD scores after controlling for ADHD-IN. The study provides the first evidence for the internal and external validity of the SCT dimension relative to the ADHD-IN dimension with teacher ratings of children from Nepal, thereby increasing the validity of the SCT construct beyond North America, Western Europe, South America, and South Korea.  相似文献   
73.
Koss  Mary P.  Leonard  Kenneth E.  Beezley  Dana A.  Oros  Cheryl J. 《Sex roles》1985,12(9-10):981-992
Sex Roles - Rape is an underreported and underconvicted crime. Therefore, many highly sexually aggressive men are missed by research employing judicial identification for sample selection. The...  相似文献   
74.
Specific language impairment in children: A cross-linguistic study   总被引:1,自引:0,他引:1  
A common profile in English-speaking specifically language-impaired children is a moderate deficit across a broad range of linguistic features and a more marked, selective impairment in using bound morphemes and components of the verb system. To gain a clearer understanding of the nature of these more serious problems, we examined the speech of monolingual Italian-speaking as well as English-speaking children with specific language impairment. The evidence suggested that phonological factors contributed significantly to these children's extraordinary problems with particular linguistic features. Contrary to expectations, other marked deficits seemed more related to the opacity of the rules involved and homonymity with other morphemes than to problems with formal grammatical devices in general or components of the verb system in particular.  相似文献   
75.

This study evaluated the internal and external validity of self-report and parent-report measures of sluggish cognitive tempo (SCT) in South Korean adolescents. Adolescents (N =?469, ages 13–17 years; 50.2% boys) completed self-report measures of SCT and attention-deficit/hyperactivity disorder inattention (ADHD-IN) in addition to measures of internalizing and externalizing psychopathology, social problems, and grades. Parents rated adolescents on SCT, ADHD-IN, internalizing and externalizing psychopathology, and social problems. Using adolescent self-report, 11 of 15 SCT symptoms showed convergent and discriminant validity with ADHD-IN. Using parent-report, all 15 SCT symptoms showed convergent and discriminant validity with ADHD-IN. For within source analyses, SCT showed unique and stronger associations than ADHD-IN with internalizing psychopathology whereas ADHD-IN showed unique and stronger associations than SCT with externalizing psychopathology. SCT and ADHD-IN showed similar unique associations with social problems, whereas ADHD-IN was more strongly related than SCT to grades. Across source analyses also supported the differential unique associations of SCT and ADHD-IN with internalizing and externalizing psychopathologies. This study provides initial evidence for the internal and external validity of SCT with South Korean adolescents, extending support for the transcultural validity of SCT to the important developmental period of adolescence.

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76.
Squirrel monkeys were trained on a multiple schedule in which 10-min periods on a continuous shock avoidance schedule, indicated by a yellow light, alternated with 10-min periods on a 1.5-min variable interval schedule of food reinforcement (VI 1.5). A white light indicated that VI 1.5 was in effect, except for the middle 2 min of the period on VI 1.5, in which a blue light appeared and terminated with the delivery of a 0.5-sec unavoidable shock. Stable response rates developed in the avoidance and VI 1.5 components. However, the highest response rates occurred in the blue, preshock stimulus. A series of experiments showed that responding in the blue stimulus persisted even when responding had been extinguished on both the VI schedule of food reinforcement and the shock avoidance schedule. Responding in the blue stimulus ceased when the blue stimulus terminated without shock or when it terminated with a response-contingent shock. Each time responding ceased, it was restored by terminating the blue stimulus with an unavoidable shock. When the blue stimulus was on throughout each session and unavoidable shocks were delivered at regular 10-min intervals, responding was well maintained. These results show that in monkeys that have been trained on a continuous avoidance schedule, unavoidable shocks can maintain responding even under conditions where responses have no programmed consequences.  相似文献   
77.
Despite the strong association between alcoholism and orality in psychoanalytic theory, use of the Rorschach Inkblot Test to provide empirical support for such a link has yielded decidedly mixed results. However, Masling's Rorschach Oral-Dependency (ROD) scale has shown twice that people with alcoholism give more oral-dependent responses on the Rorschach than matched comparison groups (Bertrand & Masling, 1969; Weiss & Masling, 1970), which is supportive of classical analytic theory. In this study, we investigated alcohol groups, depression groups, and "normal" undergraduates with the ROD scale and found that the 2 clinical groups produced higher ROD scores than the undergraduates. In addition, recent studies by Duberstein and Talbot (1993) and Fowler, Hilsenroth, and Handler (1996) provide evidence for an object relations model of dependency that suggests that a balance between anaclitic dependence and complete independence, in which dependency needs are acknowledged but are not overwhelming, is most adaptive. This model of dependency was evaluated; it was found that a simple difference in group means provided a better fit with the data, although some evidence of an object relations model also was found. Finally, Rorschach and MMPI-2 (Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989) levels of general defensiveness and primary process manifestations in Rorschach content were investigated to assess whether participants were responding defensively to the testing and whether there were any differences in the nature of oral-dependent responses between the clinical groups.  相似文献   
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