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91.
Corina J. Logan Alexis J. Breen Alex H. Taylor Russell D. Gray William J. E. Hoppitt 《Learning & behavior》2016,44(1):18-28
New Caledonian crows make and use tools, and tool types vary over geographic landscapes. Social learning may explain the variation in tool design, but it is unknown to what degree social learning accounts for the maintenance of these designs. Indeed, little is known about the mechanisms these crows use to obtain information from others, despite the question’s importance in understanding whether tool behavior is transmitted via social, genetic, or environmental means. For social transmission to account for tool-type variation, copying must utilize a mechanism that is action specific (e.g., pushing left vs. right) as well as context specific (e.g., pushing a particular object vs. any object). To determine whether crows can copy a demonstrator’s actions as well as the contexts in which they occur, we conducted a diffusion experiment using a novel foraging task. We used a nontool task to eliminate any confounds introduced by individual differences in their prior tool experience. Two groups had demonstrators (trained in isolation on different options of a four-option task, including a two-action option) and one group did not. We found that crows socially learn about context: After observers see a demonstrator interact with the task, they are more likely to interact with the same parts of the task. In contrast, observers did not copy the demonstrator’s specific actions. Our results suggest it is unlikely that observing tool-making behavior transmits tool types. We suggest it is possible that tool types are transmitted when crows copy the physical form of the tools they encounter. 相似文献
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The effects of method of reproduction, status of researcher, and personalization of signature on the initial rate of return of mail questionnaires were investigated, using a one-page combination cover letter and questionnaire mailed to 600 professors at the University of Maryland, College Park. The levels of each experimental variable were: Status — professor, graduate student; signature — hand signed in ink, mimeographed facsimile; reproduction — typed, photocopied, mimeographed.A response rate of 69% was obtained without using any follow-up procedures. Chi square analyses indicated no significant differences in the rate of returns for the levels of any of the experimental variables.It appears that initial return rate will not be significantly affected by using the most efficient, least expensive method available. 相似文献
94.
Income levels and percentage change in 1971–1975 income were regressed on personal and institutional variables for husband and wife doctorates holding full-time academic positions. Results of the composite equation indicate a $1,254 premium associated with being male after controlling for the other variables. Composite results also indicate a negative relationship between income for one spouse and the perceived opportunities for employment of the other spouse. Separate equations for the spouses indicate that this result related only to the wives' perceived opportunities of their husbands' income. By eliminating individuals with education doctorates and substituting the husbands' weights for the wives', the $1,254 differential was partially eliminated. The remaining differential between husbands' and wives' income was due to the greater involvement of the males in consulting and administration, greater involvement of the women in education, and fewer number of years of full-time experience of the wives. Comparison of income changes in both the composite and separate equations indicate that the wives received an 8–9% greater income increase than their husbands. 相似文献
95.
William J. Meyer Patrick Morrison Anayansi Lombardero Kelsey Swingle Duncan G. Campbell 《Journal of College Student Psychotherapy》2016,30(3):197-205
Unwillingness to share depression experiences with primary care physicians contributes to the undertreatment of depression. This project examined college students’ reasons for depression nondisclosure to primary care providers (PCPs). Undergraduate participants read a vignette describing someone with depression and completed measures of disclosure barriers. Analyses indicated 26% of respondents would NOT disclose depression symptoms to PCPs. Reasons for nondisclosure included difficulty initiating the depression conversation, medication aversion, and fear of referral to a psychologist. Also, anger toward the vignette character varied with disclosure willingness, suggesting that nondisclosers feel more stigma than disclosers and are less likely to engage in psychotherapy. Because engagement in pharmacological and/or psychotherapeutic treatment requires identification of depression in healthcare settings, increased understanding of disclosure barriers could increase students’ access to depression treatment. 相似文献
96.
This paper reports part of an investigation into how tertiary‐level distance students use and learn from textual materials during actual study sessions. Methods used provided biographical data on students and students' perceptions of their study approaches and access to the moment‐by‐moment thinking of students during study. Close‐ups of students at work provided by analysis of these data were not flattering. They revealed that students were satisficers, processed text at a rate consistent with a surface approach, avoided in‐text questions and activities wherever possible and made limited use of aspects of the text's access structure. Reasons for the poorer‐than‐expected study performances are considered as well as ways of improving text design to enhance the quality of learning. 相似文献
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In seven experiments, 2 squirrel monkeys were given choices between arrays of food that varied in the quantity offered. In Experiments 1-5, the monkeys were offered choices between quantities of the same food that varied in a 2:1 ratio. The squirrel monkeys failed to show the temporal myopia effect or a decrease in preference for the larger quantity as the absolute number of food items offered increased. Even when given choices of 8 versus 16 peanuts and 10 versus 20 peanuts, both monkeys significantly preferred the larger quantity. An examination of the monkeys' rates of consumption indicated that 20 peanuts were consumed over a 1- to 2-h period, with eating bouts separated by periods of nonconsumption. In Experiments 6A, 6B, and 7, food was either pilfered or replenished 15 min after an initial choice, so that choice of the smaller quantity led to more total food in the long run. These manipulations caused both monkeys to reduce choice of the larger quantity, relative to baseline choice. The results suggest that squirrel monkeys anticipated the future consequences of their choices. 相似文献