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One way to increase choice of healthy over unhealthy behaviors is to increase the cost of less healthy alternatives or reduce the cost of healthier alternatives. The influence of price on purchases of healthy and unhealthy foods was evaluated in two laboratory experiments. In Experiment 1, thirty-two 10- to 12-year-old youth were given $5.00 and allowed to purchase multiple portions of a healthy food (fruit or vegetable) and a less healthy food (higher-fat snack). The price of one type of food varied from $0.50 to $2.50, while the price of the other type was held at $1.00. Increasing the price of a type of food reduced purchases of that type of food, but did not lead to substitution with the alternative type of food. In Experiment 2, twenty 10- to 14-year-old youth were given $1.00, $3.00, and $5.00 to purchase healthy and unhealthy foods. The price of each food was raised and lowered by 25% and 50%. Raising the price of healthy or unhealthy foods resulted in decreased purchases of those foods, and income available interacted with price to predict the pattern of substitution of alternative foods. These results show the potential for controlled laboratory studies of price and food purchases, and show that the substitution of healthier for unhealthy food is related to available money.  相似文献   
994.
Two studies examined whether chronic and situational expectations about being stigmatized predict attention toward cues that are threatening to social identity. In Study 1, women's chronic expectations about experiencing sexism were positively associated with their attention toward subliminal cues threatening to their social identity. In Study 2, women were vigilant toward subliminal cues threatening to their social identity when the experimental situation conveyed that their gender was devalued, but not when the experimental situation promoted value and respect for their gender. Women were vigilant toward consciously presented cues threatening to their social identity regardless of the attitudes the experimental context conveyed toward their group. These studies have important theoretical and practical implications for understanding the psychological experience of possessing a devalued social identity.  相似文献   
995.
Recent studies have shown that persisting deficits remain even in young children with mild brain injuries. Our 2-year study investigated patterns of recovery in children and adolescents with ABI over the past 10 years. In the first year, we retrospectively reviewed demographic information (e.g., age at injury, gender,severity, GCS, coma length, and LOS), medical status, academic and therapy interventions, psychological, emotional and cognitive,physical, social, and family issues reported by parents and clients and outcome data from an adapted version of the Mayo-Portland Adaptability Inventory.In the second year of the study, we prospectively collected in-depth information through the use of new outcome measures, questionnaires and structured interviews. We focused on the relationships between persisting limitations (academic performance, pragmatic communication, social interactions, and physical abilities) and restrictions on participation (i.e., school, social relationships, vocational,and quality of life) of children who are between 3 and 5 years post-injury.  相似文献   
996.
The presentation of a subset of learned items as retrieval cues can have detrimental effects on recall of the remaining items. For 2 types of encoding conditions, the authors examined in 3 experiments whether such part-list cuing is a transient or a lasting phenomenon. Across the experiments, the detrimental effect of part-list cues was consistently found to be transient with a high degree of interim associations and lasting with a low degree. These results indicate that the persistence of part-list cuing depends on encoding, thus challenging both strategy disruption and retrieval inhibition as general accounts of part-list cuing. A 2-mechanism account is provided according to which the 2 mechanisms mediate the effect in different encoding conditions.  相似文献   
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In most studies on animal learning, individual animals are tested separately in a specific learning environment and with a limited number of trials per day. An alternative approach is to test animals in a familiar environment in their social group. In this study, the authors--applying a fully automated learning device--investigated voluntary, self-controlled visual shape discrimination learning of group-housed dwarf goats (Capra hircus). The majority of the tested goats showed successful shape discrimination, which indicates the adaptive value of an effective learning strategy. However, in each group, a few individual goats developed behavioral strategies different from shape discrimination to get reward. Relocation impairs memory retrieval (probably by attention shifting) only temporarily for previously learnt shapes. The results demonstrate the usefulness of a self-controlled learning paradigm to assess learning abilities of social species in their normal social settings. This may be especially relevant for captive animals to improve their welfare.  相似文献   
999.
The present study evaluates the extent to which central categories explicitly labeled as being in the middle of the other response categories, specifically Middle Level and Sometimes, function as expected according to the integer scoring system. The assumptions are tested by means of Bock's Nominal Model in two 5-response scales. Results show that the assumption of the ordering of the response categories is met for all the items. The ordering of thresholds is satisfied for all but one item with the central category Middle Level . Results are compared with those obtained when middle categories are not explicitly labeled as being in the middle of the other response categories, as in the case of Not Sure , Undecided or?  相似文献   
1000.
This investigation aims at adapting the test for Efficient Personality in educational contexts to Chilean reality. This instrument measures the construct efficient personality , made up of four levels of the self: strengths, requests, challenges and relationships. The original version has 58 items. In order to adapt it to our reality, 30 items were modified. The instrument was applied to a sample of 594 third and fourth secondary level students from four educational institutions of Vi?a del Mar. The new version of the instrument (23 items) presents a .85 reliability coefficient. The factorial analysis shows a structure of four basic factors which explain 50.42 % of the total variance. These factors, which are very similar those proposed in the original instrument, are named as academic self realization, social self realization, solving efficiency, and self steem. The second order factors analysis reveals a single factors structure that explains 43,28 % of the total variance, thus confirming the presence of the only factor that would correspond to the efficient personality construct presented.  相似文献   
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