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301.
The primary objective of this study was to examine the combination of acculturation, family functioning, and parental smoking as predictors of smoking attitudes and behaviors among Asian-American adolescents. The participants were 106 Asian-American high school students whose ages ranged from 15 to 19 (51 male and 55 female, mean age = 16.30 years). Of the sample, 49% reported having tried smoking, and 27% identified themselves as regular smokers. The results indicated that smoking attitudes were significantly associated with smoking behaviors. Compared to nonsmokers, adolescent regular smokers had more positive smoking attitudes, lower acculturation, poorer family functioning and were more likely to have a father who smoked.  相似文献   
302.
This set of studies explored the influence of temporal context across multiple-chain and multiple-successive-encounters procedures. Following training with different temporal contexts, the value of stimuli sharing similar reinforcement schedules was assessed by presenting these stimuli in concurrent probes. The results for the multiple-chain schedule indicate that temporal context does impact the value of a conditioned reinforcer consistent with delay-reduction theory, such that a stimulus signaling a greater reduction in delay until reinforcement has greater value. Further, nonreinforced stimuli that are concurrently presented with the preferred terminal link also have greater value, consistent with value transfer. The effects of context on value for conditions with the multiple-successive-encounters procedure, however, appear to depend on whether the search schedule or alternate handling schedule was manipulated, as well as on whether the tested stimuli were the rich or lean schedules in their components. Overall, the results help delineate the conditions under which temporal context affects conditioned-reinforcement value (acting as a learning variable) and the conditions under which it does not (acting as a performance variable), an issue of relevance to theories of choice.  相似文献   
303.
Research on persuasion has shown that for attitudes to change people need to take into consideration not only the thoughts message recipients generate in response to proposals but also how people think about their own thoughts (metacognition). In the present research, we introduce a new perspective for improving outgroup attitudes focused on the distinction between cognition and metacognition but this time applied to the perceptions of others’ minds. Specifically, we examined to what extent thinking about the mental processes of outgroup members influences attitudes towards those outgroups. We compared the impact of thinking about how others think (perceived primary cognition) with how others think about their own thoughts (perceived secondary cognition or metacognition). In the primary cognition treatment, participants answered questions about the thinking processes of outgroup members. In the secondary cognition treatment, participants answered questions that required them to consider how outgroup members think about their own thoughts (i.e., metacognition). Compared to controls, these treatments were capable of improving attitudes of Spanish citizens towards Syrian refugees, South American immigrants, and Roma people. A third study used a minimal group paradigm in which a fictitious outgroup was described as having primary (vs. secondary) cognition. A final study also tested the implications of assuming that groups have one type of cognition or another. The effects of the two treatments varied depending on the type of outgroup.  相似文献   
304.
Smoking is the primary preventable cause of death, and yet 3,000 adolescents become smokers each day. Most adult smokers begin this deadly habit when they are under the age of 18, which is the minimum legal age for the purchase of cigarettes. The majority of adolescent smokers are able to purchase cigarettes even though laws prohibit the sale of cigarettes to minors. In the late 1980s, Woodridge, IL, became one of the first towns in the nation to demonstrate a significant reduction in the ability of youth to purchase cigarettes. Almost 2 years after passage of this legislation, the percentage of regular smokers among 7th- and 8th-grade students had been reduced from 16 to 5%. Seven-year follow-up data in a sample of high school youths indicate that youths living in communities with regular enforcement had significantly less smoking than those living in communities without regular enforcement. In particular, rates of regular smoking were 8.1% in communities with regular enforcement versus 15.5% in communities without regular enforcement. It is possible that adolescents who had restricted access to tobacco products were less likely to become regular smokers. These findings have important public health implications, particularly in light of recent federal legislation mandating that all states develop programs to reduce access of youth to tobacco products.  相似文献   
305.
Theory Reduction in the Social Sciences. The example of balance theories. A central topic both in philosophy of science as well as in the empirical sciences is the reconstruction of the relations between theories. In the past comparisons of theories by means of traditional linguistic methods have proved to be extremely difficult and complicated. In this article the reconstruction of intertheoretical relations based on model-theoretical terms is propagated, as formulated within the structuralist view of theories. The efficiency of a model theoretical based comparison of theories is demonstrated by two theory elements from the social science research program of balance theories: The basic element by Heider and the transitivity theory by Holland and Leinhardt. First of all both theory elements are introduced informally and reconstructed in the structuralist format. On the basis of these reconstructions can be shown, that the Heider theory can be formally reduced to the Holland-Leinhardt theory and that the theory younger in history means an improvement. However, an integration of all balance theoretical elements into a theory net is not possible. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
306.
Models of choice in concurrent-chains schedules are derived from melioration, generalized matching, and optimization. The resulting models are compared with those based on Fantino's (1969, 1981) delay-reduction hypothesis. It is found that all models involve the delay reduction factors (T - t2L) and (T - t2R), where T is the expected time to primary reinforcement and t2L, t2R are the durations of the terminal links. In particular, in the case of equal initial links, the model derived from melioration coincides with Fantino's original model for full (reliable) reinforcement and with the model proposed by Spetch and Dunn (1987) for percentage (unreliable) reinforcement. In the general case of unequal initial links, the model derived from melioration differs from the revised model advanced by Squires and Fantino (1971) only in the factors affecting the delay-reduction terms (T - t2L) and (T - t2R). The models of choice obtained by minimizing the expected time to reinforcement depend on the type of feedback functions used. In particular, if power feedback functions are used, the optimization model coincides with that obtained from melioration.  相似文献   
307.
Responding on concurrent-chains schedules in open and closed economies.   总被引:1,自引:1,他引:0  
Pigeons' key pecks were reinforced according to concurrent-chains schedules of reinforcement. The programmed average time from the onset of the initial links to a terminal link entry was held constant across conditions while the value of variable-interval schedules in the terminal links was varied. Performance was assessed under two economic conditions: (a) an open economy in which session duration was limited to 1 hr and subjects were maintained at 80% of their free-feeding body weights with postsession food when necessary; and (b) a closed economy in which sessions were 23.5 hr long and no deprivation regimen was in effect. In all cases, the relative rate of responding in the initial links matched the reduction in overall delay to primary reinforcement correlated with entry into one terminal link relative to the reduction in delay correlated with entry into the other terminal link. Although the sum of responses made in the initial links and terminal links was found to increase, then decrease, as the rate of food presentation decreased in the closed economy, there was no consistent effect of overall rate of food presentation on total responding in the open economy. The choice data suggest that relative delay reduction predicts choice accurately, regardless of economic context.  相似文献   
308.
A self-administered mood management intervention program for smoking cessation provided through the mail to Spanish-speaking Latinos resulted in a 23% abstinence rate at 3 months compared to an 11% abstinence rate for a smoking cessation guide alone. Participants (N = 136) were randomly assigned to receive either the cessation guide (the Guía), or the Guía plus a mood management intervention (Tomando Control de su Vida) presented in writing and in audiotape format. At 3 months after random assignment, 16 out of 71 of those assigned to the Guía-plus-mood management condition reported being abstinent (not smoking for at least 7 days) compared to 7 out of 65 in the Guía-only condition (z = 1.8; p = .04, one-tailed). Moreover, those with a history of major depressive episodes, but not currently depressed, reported an even higher abstinence rate in the Guía-plus-mood management condition, compared to the Guía-only condition (31 vs. 11%, z = 1.8, p = .04, one-tailed). We conclude that the mood management mail intervention substantially increases abstinence rates, especially for those with a history of major depressive episodes.  相似文献   
309.
Passive smoking has been shown to be hazardous to the health of nonsmokers. Given this documented link between exposure to smoke-filled environments and deleterious health consequences, there is a need to develop effective procedures that establish and maintain no-smoking areas in various public settings. The present study focused on decreasing cigarette smoking in a section of a university cafeteria. Posting of no-smoking signs was found to decrease levels of smoking only minimally. However, when smokers were verbally prompted not to smoke, in the presence of the signs, marked decreases in smoking occurred in the target area.  相似文献   
310.
The effects of two different procedures for reducing elevator energy use were assessed using a multiple-baseline design. In the first procedure, feedback about the amount of energy consumed by the elevators each week was posted on each elevator door. Later, signs advocating the use of stairs to save energy and improve health were posted next to the feedback signs. In the second procedure, the time required to travel between floors was increased by adding a delay to the elevator door closing mechanisms. Results indicated that neither feedback alone nor feedback plus educational signs reduced the amount of energy consumed by the elevators. However, use of the door delay reduced consumption by one-third in all elevators.A second experiment replicated the effect of the door delay on energy consumption and, in addition, demonstrated that the door delay also produced a reduction in the number of persons using the elevator. The second experiment also showed that, following an initial period during which a full delay was in effect, a gradual reduction of the delay interval resulted in continued energy conservation. Reduced convenience as a general strategy for energy conservation is discussed.  相似文献   
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