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901.
Do young boys and girls understand what leads to academic success (e.g., talent, effort, good teaching, luck) in the same way? Do young girls and boys have equivalent perceptions of their academic competence? Are these beliefs engendered in the same way across sociocultural contexts? In a cross-cultural study of over 3,000 children in grades 2 to 6, ages 7.2 to 13.6, we discovered that boys and girls around the world have very similar ideas about what generally leads to academic success. Moreover, in the few contexts where boys' and girls' academic performances were equal, their beliefs were also equal. However, when girls outperformed boys, their beliefs in their own talent were no greater than boys' beliefs, even though they did have stronger beliefs than boys in other facets of their achievement potential (e.g., putting forth effort, being lucky, getting their teacher's help). Our findings support the generally close correspondence between children's achievement and their competence-related beliefs, with the exception that young girls appear to specifically discount their talent. The effects held regardless of the children's achievement, intelligence, or age (approximately 8 to 13 years). Girls were more biased in some contexts than in others, however, suggesting that competence-related biases are rooted in culture-specific aspects of school settings.  相似文献   
902.
Attachment relationships of toddlers (N = 45) to their child-care providers were investigated. Children's behaviors with their mothers were observed at home at 24 months and with their child-care providers at 26 months. Attachment Q-Sort procedures were used at home (90 items) and in child care (78 items); the latter yielded a 15-item Safe and Secure Scale describing the safe haven and secure base functions of attachment relationships in child care—being able to (a) seek and receive positive attention, (b) feel safe and protected, (c) receive support for exploration, (d) receive consolation when distressed, and (e) seek and accept assistance. Independent observational measures of child-care quality also were obtained at 24 months. As hypothesized, the Safe and Secure Scale was related to proximal rather than distal indicators of child-care quality, and it was a stronger measure than the child-caregiver Q-security score that was based on all 78 items. Child-mother and child-caregiver security were significantly related.  相似文献   
903.
Microcounseling techniques were used to conduct an experimental study. The objective was to train naive college students who were interested in counseling to assess clients' attitudes toward guidance tests. A correlation of .797 was obtained between clients' ratings of attitudes toward tests and the trainees' ratings of clients' attitudes toward tests. Findings were consistent with the results of other microcounseling studies. Individual differences among the trainees were noted and comparisons were made between the trainees' own ratings, judges' ratings, and clients' ratings of trainees. Lack of a control group imposes a serious limitation on interpretation of the results.  相似文献   
904.
905.
Purpose: To describe the results of showing farmer learning videos through different types of volunteers.

Design/Methodology/Approach: Semi-structured interviews with volunteers from different occupational groups in Bangladesh, and a phone survey with 227 respondents.

Findings: Each occupational group acted differently. Shop keepers, tillage service providers, agricultural input and machine dealers reached fairly small audiences. Tea stall owners had large, male audiences. Non-governmental organisations and community-based organisations, reached more women. The cable TV (dish-line) operators showed the videos on local TV, but some were reluctant to do so again. The Union Information Service Centres showed the videos and reached women viewers. Half of the official government extension agents surveyed also showed the videos publically.

Practical Implication: This video featured maize, wheat and rice seeding machinery. Because the machinery is complex and requires hands-on training, this first video aimed to expose tillage and sowing service providers and farmers to the machinery, without trying to teach them how to use it. But some farmers were so interested that they watched the video many times to learn more about the equipment. Before farmers and service providers decide to buy machinery for direct seeding, they still want to see and learn from demonstration plantings, to examine first-hand how the crop behaves when planted with the new equipment.

Originality/Value: Video can be an effective way of sharing high-quality information with a large audience, if properly distributed.  相似文献   

906.
Recent research on principles of best practice for designing effective multimedia instruction has rarely taken into account students’ alternative conceptions, which are known to strongly influence learning. The goal of this study was to determine how well students of quantum mechanics could learn ‘vicariously’ by watching a student-tutor dialogue based on alternative conceptions. Two video treatments were created to summarize key aspects of quantum tunneling, a fundamental quantum mechanical phenomenon. One video depicted a student-tutor dialogue, incorporating many of the common alternative conceptions on the topic, and resolving inconsistencies in reasoning through discussion. The other presented the same correct physics material in an expository style without alternative conceptions. Second year physics students were randomly assigned to one of the two treatments and were tested before and after watching the video during a lecture. Results show a statistically significant (p < .01) advantage for the learners in the dialogue treatment (d = 0.71). Follow-up interviews of students yielded insight into the affective and cognitive benefits of the dialogue video.  相似文献   
907.
The goals of this research were to explore the current literature regarding associations between psychological stress and adverse fetal outcome, associations between aerobic exercise and psychological stress reduction, and associations between aerobic exercise and fetal outcome. The published studies that were located provide evidence of the following: 1) Stress reactivity increases physiologically during pregnancy, 2) pregnant women may experience additional stressors that are usually not experienced in a nonpregnant state, 3) psychological stress in pregnancy is associated with adverse fetal outcome, 4) exercise can be a method of stress reduction, 5) exercise in pregnancy is not associated with adverse fetal outcome, and 6) exercise in pregnancy may provide benefit to the fetus. Data were analyzed from an original study and associations were reported between psychological stress-management activities and participation in aquatic aerobic exercise classes. No reports were available investigating an exercise-induced reduction in psychological stress with fetal outcome.  相似文献   
908.
This study examines the organizational characteristics of 51 higher education institutions in relationship to student performance and growth. The study first finds that organizational measures of mission, size, wealth, complexity, and selectivity are statistically represented by the 2-year versus 4-year college mission. Findings indicate that 2-year and 4-year campuses indeed do exert significantly different influences on undergraduate GPA and self-reported intellectual growth. Next, the study uses both OLS regression and HLM to examine these influences. High school percentile rank and college classroom experiences are better predictors of Cum GPA at 4-year institutions, while student effort is a better predictor of GPA at 2-year institutions. Whereas the most important predictors of Cum GPA include precollege measures such as high school percentile rank and SAT score, the most influential predictors of student intellectual growth are campus experiences including classroom vitality, peer support, student effort, commitment, and involvement. Controlling for all other variables, students at 2-year institutions receive higher grades, and students at 4-year campuses experience more growth.  相似文献   
909.
INTRODUCTION It is well-known from the genetic code structure that there exists a connection between codons and physical and chemical amino acid properties (Lewin, 1983). Codon properties in turn are defined by physical properties of the nucleotides from which they are compounded (Ratner, 1985; 2000). The most important properties of nucleotides as complex three-dimensional molecules are their dipole moment, heat of formation and energy of the most stable con- formation (Schneider and Be…  相似文献   
910.
Pigeons categorized binomial samples produced by two complementary random processes. Samples were 1, 2, 4, or 8 successively presented outcomes (vertical or horizontal lines) of, in effect, tossing one of two equally likely coins. One coin (A) was biased in favor of vertical, and the other coin (B) was similarly biased in favor of horizontal. Choosing red or green stimuli presented after each sample was reinforced with food if coin A or coin B had been tossed, respectively. In that sense, choosing red or green was logically analogous to inferring that the statistical evidence reflected tossing of coin A or coin B, respectively. The statistical diagnosticity of a sample, the relative likelihood of its having been produced by a particular coin, equaled, except for sampling fluctuation, the relative frequency of reinforcement of a particular color given that sample, and was experimentally varied by the bias on the coins and by sample size. All the variables that affect optimal, formal inference about binomial samples also affected intuitive inference. But inferences were very suboptimal: “undermatching” was obtained in part due to control of categorization by the sequential structure of binomial samples. These results reveal limitations of optimality theories for animal decision making in the face of uncertainty when observations in samples are presented successively. On the other hand, they are generally compatible with molecular analyses of instrumental learning which assign an important role to the local temporal organization of events preceding reinforcement. Most generally, they show that maladaptive control over intuitive statistical inference by a variable upon which optimal performance does not depend is neither a uniquely human phenomenon nor dependent upon linguistic strategies.  相似文献   
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