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991.
Two major classes of models have been proposed to explain concept learning: strength models and distance models (Hayes-Roth & Hayes-Roth, 1977). The present study demonstrates that subjects abstract transformation rules as defined by the Franks and Bransford 11971) distance model. Transformation rules characterize how the patterns of a concept differ from each other. Transformation rules are inconsistent with strength models, which assume that subjects abstract component features and not relational information characterizing the differences among patterns. Whether a strength model or a distance model is more appropriate in other instances of concept learning is probably a function of task demands, stimulus characteristics, and subject characteristics.  相似文献   
992.
Natural conversations in first-grade classrooms are analyzed. Exchanges that are initiated and extended by questioning are the focus of attention, and analyses are directed principally to a comparison of adult-initiated and child-initiated interrogative series. Differences in structural features are found for each component utterance of an interrogative unit of discourse, namely, question, response, and confirmation. Adults ask more constraining questions than children, and children respond in more complex although less appropriate ways to children's questions than to adults' questions. The type of discourse within which an utterance is located influences the features of children's responses to children's but not to adults' questions. These differences are interpreted as reflecting differences in the relative power of adults and children in these settings.This work has been supported by a grant from the National Science Foundation for research on Social Effects on Language and Communication, Grant No. GS-3001.  相似文献   
993.
This study investigated how causal belief for prior success or failure affected preferences to delay gratifications in task contingent versus task noncontingent conditions. Success or failure on the Treatment Task and belief about the outcome were experimentally induced to lead fourth-and fifth-grade pupils to perceive task performance as resulting from one of four factors (Ability, Task Difficulty, Effort, or Luck). Thereafter, each subject chose between smaller, noncontingent rewards and delayed, larger rewards that were contingent on waiting only or on successful performance on tasks which varied in similarity to the initial task. As predicted, preferences to delay were not differentially affected by success or failure when subjects believed unstable factors of effort or luck caused the outcome. However, delay was affected by prior success or failure when the belief was that the outcome resulted from stable factors of ability or task difficulty, with subjects delaying more after success than following failure. Furthermore, the outcome predicted delay on tasks identical or similar to the Treatment Task whereas belief about causality predicted delay on the Different Task. Delay was greater by subjects with ability or effort inductions than by subjects with a luck induction.  相似文献   
994.
Sixty children were individually administered the Matching Familiar Figures Test and the Bender Gestalt Test. The mean age of the subjects was 10 years, 11 months. A significant relationship was found between errors on the Bender Gestalt test and impulsivity. More specifically, increased or decreased loops (figure four or six), change in angulation, loops for circles and circles for dots or dots for circles were all significantly related to children's impulsivity.  相似文献   
995.
One hundred nonpatient adults, screened for evidence of personality disorganization, were retested after a three-year interval to study the temporal consistency of the Rorschach. In general, the correlational analysis for 19 basic variables studied, and a directionality analysis for five ratios, illustrate a considerable sturdiness over time. It is postulated that these variables can be separated into situational related indices (state variables), and more stable scores indicative of durable response styles (trait variables), based on the assumption that variables with lower correlations would identify state variables, while the higher correlations would signify the trait features. Nine of the 19 variables yield retest correlations in excess of.  相似文献   
996.
The retention characteristics of fast and slow movements were investigated in two experiments. Experiment 1 examined the reproduction of either fast or slow preselected movement rates after 0-sec rest, 15-sec rest or a 15-sec filled delay. Both fast and slow movement rates were rehearsable. Experiment 2 examined reproduction accuracy after subjects were required to perform a competing secondary task during the production of fast and slow movements. Although the secondary task degraded the reproduction of slow movements, it had no apparent effect upon the reproduction of fast movements. These results were interpreted as indicating partial support for Jones' (1974) notion of central monitoring of efference, and suggested that the contribution of proprioceptive feedback to movement control varies as a function of movement rate.  相似文献   
997.
998.
The relationship between levels of frontalis muscle activity and self-reports of pain was evaluated in two studies. In Study I frontalis muscle activity and self-reports of pain collected during biofeedback treatment of muscular contraction headache clients were correlated. In Study II frontalis EMG activity was increased and decreased using biofeedback techniques while concurrent reports of headache pain were recorded. The results of Study I indicated a significant relationship between EMG activity and reported headache pain for only two of the five subjects studied. The biofeedback procedures in Study II were associated with reliable increases and decreases in EMG activity. Concordance between EMG and pain reports occurred only during the EMG increase condition. Overall correlations were significant for one of the 2 subjects. The results suggest that EMG activity may not be sufficient to account for pain reports in all chronic headache clients, and variables other than EMG activity may be influencing reports of pain in some patients.  相似文献   
999.
1000.
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