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991.
Three studies were conducted to assess the proposition that self-esteem serves an anxiety-buffering function. In Study 1, it was hypothesized that raising self-esteem would reduce anxiety in response to vivid images of death. In support of this hypothesis, Ss who received positive personality feedback reported less anxiety in response to a video about death than did neutral feedback Ss. In Studies 2 and 3, it was hypothesized that increasing self-esteem would reduce anxiety among individuals anticipating painful shock. Consistent with this hypothesis, both success and positive personality feedback reduced Ss' physiological arousal in response to subsequent threat of shock. Thus, converging evidence of an anxiety-buffering function of self-esteem was obtained.  相似文献   
992.
The effects of reinforcement schedules on rats' choice behavior in extinction were studied. In a free-operant chamber equipped with two retractable bars, the experimental animals were trained to press the bars separately for a food reward. One bar delivered the reward on a continuous reinforcement (CRF) schedule, and the other delivered the reward on a partial reinforcement (PRF) schedule. Control animals earned the reward from both bars with the same reinforcement schedule, either a CRF or a PRF. When both bars were simultaneously available during extinction, the experimental animals responded more frequently to the CRF than to the PRF alternative, demonstrating a reversed within-subjects partial reinforcement extinction effect (PREE). A conventional between-subjects PREE was replicated in the control subjects. The results of this study were inconsistent with both Amsel's (1962, 1967) frustration hypothesis and Capaldi's (1966, 1967) sequential hypotheses.  相似文献   
993.
The Wonderlic Personnel Test (1983) was administered twice over a 3-week period under conditions in which the activity of the second test was experimentally manipulated. Data from 302 undergraduates were analyzed. The standard test-retest reliability coefficient, .872, was not significantly different from the coefficients obtained from three other groups that, on the second test, were each given specific instructions: (a) to reason out the answers (pure reassess condition); (b) to use reasoning, memory of their initial responses, or both (reassess and memory); or (c) to take an alternate form of the test (parallel). However, the standard test-retest reliability coefficient was higher, p less than .10, than the coefficient obtained from a condition (pure memory) in which subjects were instructed to duplicate their previous responses, using only memory. Although the subjects in the test-retest and combined reassess and memory conditions reported recalling previous answers for 20-25% of the items on the second test, it was concluded that conscious repetition of specific responses did not seriously inflate the estimate of test-retest reliability.  相似文献   
994.
In this study, the authors assessed the relation of parental reinforcement and parental values to young children's prosocial behaviors. Parents' dyadic interactions with their 1- to 2-year-old children were videotaped in the home on two occasions approximately 6 months apart. The children also were videotaped playing with a peer at 3 1/2 to 4 1/2 years of age. Parental reinforcement of the children's prosocial behaviors was coded, as were the children's prosocial behaviors with the peer. The frequency of girls' spontaneous prosocial behaviors decreased in the early years; modest consistency was observed for boys (but not girls) across the two parental sessions. No relation existed between the frequency of children's prosocial behaviors with their parents and their behaviors with peers. Both maternal and paternal valuing of compliance were negatively related to the mothers' use of reinforcement for children's spontaneous prosocial behaviors. Parental reinforcement of compliant prosocial behaviors was negatively related to children's compliance with a peer's request for prosocial behavior and positively related to defensive behavior with the peer. Fathers' valuing of prosocial behavior was associated with children's compliance with the peer's requests for prosocial action. Parents who valued compliance had children who exhibited low levels of compliant prosocial behaviors with the peer, possibly because of the depressed level of peer interaction.  相似文献   
995.
This study compared Piagetian cognitive development in normal achieving children and two groups of children with learning disabilities designated as either auditory-linguistic or visual-spatial on the basis of Verbal-Performance IQ differences on the Wechsler Intelligence Scale for Children-Revised (WISC-R; 1974). The two groups with learning disabilities were matched with normal achieving controls on intelligence, socioeconomic status, sex, race, and age. Piagetian tasks measuring conservation, seriation, and classification were administered to each child to determine level of operative thought. The auditory-linguistic group scored significantly below normal controls in operativity, and significantly fewer were at a concrete operational level on a conservation of length task than were normal achieving children. The visual-spatial group did not differ significantly from normal controls. These results suggest that auditory-linguistic disabilities may be more detrimental than visual-spatial disabilities to development of operativity.  相似文献   
996.
We explored the low correlation among different types of childhood depression measures at the item level. The items from the Children's Depression Inventory (CDI), Peer Nomination Inventory of Depression (PNID), and the Child Behavior Checklist-Teacher Report Form (CBCL-T) were combined, and both first- and second-order factor analyses were conducted. Results indicate that self-report, peer-report, and teacher-report assessments of depression measure generally uncorrelated constructs. Second-order analysis suggests that depression as a global construct is being measured to some degree by items from all three instruments. Canonical analysis was employed to identify items that best predicted CDI, PNID, and CBL-T summary scores simultaneously. Also, the relationship between specific items with similar content was investigated. Results from these analyses generally supported a conclusion that the three types of measures yield scores that are primarily independent and that the use of summary scores is not masking stronger relationships within measures. These findings have implications for clinical practice and construct elaboration.  相似文献   
997.
While looking through laterally displacing prisms, subjects pointed 60 times straight ahead of their nose at a rate of one complete movement every 2 or 3 s, with visual feedback available early in the pointing movement or delayed until the end of the movement. Sagittal pointing was paced such that movement speed covaried with pointing rate. Aftereffect measures (obtained after every 10 pointing trials) showed that when the limb became visible early in a pointing movement, proprioceptive adaptation was greater than visual, but when visual feedback was delayed until the end of the movement, the reverse was true. This effect occurred only with the 3-s pointing rate, however. With the 2-s pointing rate, adaptation was predominately proprioceptive in nature, regardless of feedback availability. Independent of the availability of visual feedback, visual adaptation developed more quickly with 3-s pointing, whereas proprioceptive adaptation developed more rapidly with 2-s pointing. These results are discussed in terms of a model of perceptual-motor organization in which the direction of coordinative (guidance) linkage between eye-head (visual) and hand-head (proprioceptive) systems (and consequently the locus of discordance registration and adaptive recalibration) is determined jointly by pointing rate and feedback availability. An additional effect of pointing rate is to determine the rate of discordant inputs. Maximal adaptive recalibration occurs when the input (pointing) rate matches the time constant of the adaptive encoder in the guided system.  相似文献   
998.
999.
ABSTRACT A taxon is a nonarbitrary class whose existence is conjectured as an empirical question, not a mere semantic convenience. Numerous taxa are known to exist in nature and society (chemical elements, biological species, organic diseases, geological strata, kinds of stars, elementary particles, races, cultures, Mendelizing mental deficiencies, major psychoses, vocations, ideologies, religions). What personality types, if any, occur in the nonpathological population remains to be researched by sophisticated methods, and cannot be settled by fiat or "dimensional" preference. The intuitive concept of taxonicity is to be explicated by a combination of formal-numerical and causal criteria. Taxometric methods should include consistency tests that provide Popperian risk of strong discorroboration. In social science, latent class methods are probably more useful than cluster algorithms.  相似文献   
1000.
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