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931.
The time doctoral students expect to take to complete their degree is investigated in a model which stresses the effects of economic factors. The model also accounts for the interdependency among such variables as employment hours, study hours, household income, and part-time study. We find that field of study, amount of borrowing, household income, and study hours have direct effects on expected time to degree. Indirect effects also occur from employment hours and the amount of fellowship, scholarship, or grant aid. When the sample is separated into foreign and U.S. students, we find that U.S. students underestimate their time to degree. Also, household incomes are higher for U.S. students and increase the time to degree, while the opposite is true for foreign students. Teaching assistantships increase the time to degree for foreign students while research assistantships reduce it.  相似文献   
932.
933.
934.
935.
In this longitudinal study, individual differences in security of attachment at 18 months and effective autonomous functioning at age 2 years were related to the dimensions of ego-control and ego-resiliency at age 4--5 years. The kindergarten or nursery school teachers of 26 children completed California Child Q-Sorts. The children were also given a short form of the Block's laboratory battery (Banta's curiosity box, level of aspiration, motor impulse control delay of gratification, the Shure and Spivack Preschool Interpersonal Problem-solving Test, and the Lowenfeld mosaics). Following the Blocks, composited ego-resiliency and ego-control scores were derived from each data set. Children earlier classified as securely attached were, as predicted, significantly higher on ego-resiliency on both laboratory and Q-sort composites. They were also higher than anxiously attached infants on 3 independent measures of curiosity. An independently composited index of competence from 2-year tool-using measures also correlated significantly with later resiliency, as did 2-year measures of mothers' support and quality of assistance. The data provide initial links between the infant's quality of attachment, the toddler's effectiveness in a problem-solving situation, and competence during the preschool years.  相似文献   
936.
Cultural expectations and sex-role standards about reading in Canada, Denmark, England, Finland, Israel, Japan, and U.S.A. were investigated. A picture test showing various activities and objects including reading and books was administered in each country to six sub-samples that approximated to the levels: students in grades I, IV, VIII, and XII, college students, and adults. Subjects had to ascribe the activity or object as being appropriate for either a boy or a girl. The results were consistent with the hypothesis that cultural expectations and sex-role standards about reading are congruent within one country but that they differ between countries. In particular, boys in Canada and the U.S.A. rapidly learn to perceive reading as a feminine activity, whereas Danish and Japanese males at all ages consistently view reading as acceptable masculine behaviour.  相似文献   
937.
A study of seriation was conducted from the perspective of Gibson's theory of perceptual development. Kindergarten children who evidenced little seriation of height or brightness were assigned to either 1 of 3 perceptual training conditions or to a fourth, control condition. Training consisted of nonreinforced same-different judgments to wooden dowels varying in height, or in brightness, or simultaneously in height and brightness. The theoretical rationale for this training was that it would facilitate perception of the stimulus dimension(s) on which the dowels differed. It was found that perceptual training did facilitate seriation, particularly if both the height and brightness dimensions varied simultaneously in training.  相似文献   
938.
To study sensitivity to radial location of an odor source, 20 human newborns, ranging from 16 to 130 hours of age, were presented with a small amount of ammonium hydroxide. The odor source was placed near the nose slightly to the left or right of midline, with its position randomized over repeated trails. Direction of headturn with respect to the odor location and diffuse motor activity were scored from the videotape recordings of the newborns' behavior. It was found that as a group, the newborns turned away from the odor source more frequently than they turned toward it. The tendency to turn away from the odor was stronger in infants who displayed less motor activity after the response. Newborns also exhibited a right bias in the direction of the head movements. It is concluded that a spatially appropriate avoidance response is present in the neonate and that the newborn is innately sensitive to the radial location of an odor.  相似文献   
939.
940.
Three experiments investigated the effects of magnitude and schedule of reinforcement and level of training in instrumental escape learning at a 24-h intertriai interval. In Experiment I, two magnitudes of reinforcement were factorially combined with two schedules of reinforcement (CRF and PRF). Under PRF, large reward produced greater resistance to extinction than did small reward, while the reverse was true under CRF. In Experiment II, two levels of acquisition training were factorially combined with three schedules of reinforcement (CRF, single-alternation, and nonalternated PRF). Patterned running was observed late in acquisition in the single-alternation extended-training condition. Resistance to extinction was greater for the nonalternated PRF condition than for the single-alternation condition following extended acquisition, and the reverse was true following limited acquisition. Experiment III confirmed the extinction findings of Experiment II. The results of all three experiments supported an analysis of escape learning at spaced trials in terms of Capaldi’s (1967) sequential theory.  相似文献   
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