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911.
Three skills which characterize cognitive functioning in human infants in the middle of the first year of life—habituation, novelty responsiveness, and cross-modal transfer—predict mental ability in later childhood. Antecedents of each skill at 5 months postnatal were examined in a short-term prospective longitudinal study of infant ability and maternal intelligence and interaction style. Infant perceptuocognitive performance at 2 months, maternal intelligence, and maternal responsiveness at 5 months relate to the expression of the three infant cognitive skills, but in different ways. Variation in infant information-processing abilities can be explained by specific child and maternal factors that are evident soon after birth. 相似文献
912.
913.
Undergraduate students from a predominantly white middle class student body who were administered the Desirability of Control Scale in 1980 completed the scale again in 1990. Males scored significantly higher on the scale than females, indicating a higher desire for control, in the initial sample. The males' scores did not differ significantly over the ten-year period. However, the female subjects' scores increased over the course of the decade to a point not significantly different from that of the males. Possible explanations of this effect concern changes in gender role expectations in the 1980's and changes in the women's preference for control following school and career experiences.Some of the data reported in this paper were presented at the annual meeting of the American Psychological Association, San Francisco, 1991.Reprint requests should be addressed to either Jerry M. Burger at Department of Psychology, Santa Clara University, Santa Clara, CA 95053, or Cecilia H. Solano at Department of Psychology, Box 7778, Wake Forest University, Winston-Salem, NC 27109. 相似文献
914.
This research was an investigation into four challenges purported to confront cross-sex friends. One hundred and thirty eight individuals (females = 86, males = 52) completed two surveys designed to explore the extent to which the sexual, emotional bond, audience, and equality challenges were present in their cross-sex friendships. Over 98% of the participants were heterosexual, 99% were Caucasian, and approximately 5% were Hispanic. Data gathered from the first survey were analyzed using a three-way analysis of variance, with gender, type of friendship, and romantic status as the independent variables, and three of the four challenges as the dependent variables. The first survey also included open-ended questions designed to explore the nature and existence of the challenges. The second survey was in a diary format. Respondents kept a frequency count for three weeks of discussions they had with their cross-sex friend concerning the challenges, and thoughts that they had as individuals concerning those challenges. Results from both surveys indicate that though the challenges exist and have powerful effects on a small percentage of individuals in cross-sex friendships, for the majority of participants the challenges are not perceived as salient. 相似文献
915.
Summary Two experiments investigated relative spatial coding in the Simon effect. It was hypothesized that relative spatial coding is carried out with reference to the position of the focus of visual attention. The spatial code for an imperative stimulus presented exactly at the position of focal attention should be neutral on the horizontal plane, and therefore no Simon effect should be observed. However, when the imperative stimulus is presented to the left or to the right of the current position of focal attention, the spatial code should not be neutral, thus producing a Simon effect. In both experiments, focal attention was manipulated either by a peripherally presented onset precue (Experiment 1) or by a centrally presented symbolic precue (Experiment 2). Results showed that the Simon effect was substantially reduced in both experiments when a valid precue preceded the imperative stimulus just in time to conclude refocusing of attention to the position of the imperative stimulus before it was presented. However, conditions with neutral precues yielded a normally sized Simon effect. In both experiments, the Simon effect decreased as the SOA grew when the precue was valid. At least for the Simon effect, the results can be interpreted as evidence that relative spatial coding is functionally related to the position of the focus of attention. 相似文献
916.
Sex Roles - Women's thoughts and feelings in response to interpersonal and environmental sexual harassment simulations from co-workers with equal or greater organizational status were explored.... 相似文献
917.
The partial credit model is considered under the assumption of a certain linear decomposition of the item × category parameters
ih into basic parameters
j. This model is referred to as the linear partial credit model. A conditional maximum likelihood algorithm for estimation of the
j is presented, based on (a) recurrences for the combinatorial functions involved, and (b) using a quasi-Newton approach, the so-called Broyden-Fletcher-Goldfarb-Shanno (BFGS) method; (a) guarantees numerically stable results, (b) avoids the direct computation of the Hesse matrix, yet produces a sequence of certain positive definite matricesB
k
,k=1, 2, ..., converging to the asymptotic variance-covariance matrix of the
. The practicality of these numerical methods is demonstrated both by means of simulations and of an empirical application to the measurement of treatment effects in patients with psychosomatic disorders.The authors thank one anonymous reviewer for his constructive comments. Moreover, they thankfully acknowledge financial support by the Österreichische Nationalbank (Austrian National Bank) under Grant No. 3720. 相似文献
918.
Four homing pigeons were trained over 5 months in a zero-delay, “arbitrary” matching-to-sample procedure with sample and comparison stimuli presented on any of three response keys. Birds were also required to complete a fixed-ratio 10 requirement on both sample and comparison stimuli to terminate their presentation. The procedure resulted in the establishment of relations that were not specifically trained and that can be characterized by the property of transitivity in a stimulus equivalence context. This result was in contrast with the findings obtained from most previous research with nonhuman subjects. 相似文献
919.
Seven undergraduates participated in a concurrent-choice experiment with monetary reinforcers. Response-independent analogues of variable-interval and variable-ratio schedules were used to assess whether subjects would maximize reinforcement rate. The optimal pattern of behavior, in terms of maximizing reinforcement rate, involved a large bias toward the ratio alternative, with only occasional sampling of the interval schedule. Most experiments with pigeons, however, demonstrate matching of response rates to reinforcement rates, with only slight biases for the ratio schedule. Although subjects in the present experiment allocated more time to the ratio alternative than required by matching, the magnitude of the bias did not approximate that predicted by a maximizing account. After exposure to clock stimuli correlated with the operation of each schedule, 1 subject's behavior did show a substantial level of bias, increasing the total number of reinforcers obtained, and lay at a point between the predictions of matching and maximizing. The other subjects, however, continued to respond less optimally. The present results can be accounted for by a view of matching that incorporates the effects of delayed reinforcement. 相似文献
920.
Using data collected from 1,987 employees at several locations of a large firm, this study investigates relationships between these employees' cognitive and attitudinal perceptions of an employee assistance program (EAP) and their propensity to use it. Familiarity with the program, perceived accessibility of it, and perceived managerial support for it are hypothesized to affect both employees' confidence in the program and their propensity to use it, and confidence in the EAP is further hypothesized to affect propensity to use. LISREL analysis supported the overall model, but the direct paths from the cognitive variables to propensity to use were not supported and confidence in the program was therefore indicated to be an essential mediating variable. Propensity to use an EAP is argued to be an important indicator of effective EAP implementation and suggestions are offered to management for promoting employee confidence in an EAP and ultimately their propensity to use it. 相似文献