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11.
Three severely mentally retarded adolescents were studied under discrete-trial procedures in which a choice was arranged between edible reinforcers that differed in magnitude and, in some conditions, delay. In the absence of delays the larger reinforcer was consistently chosen. Under conditions in which the smaller reinforcer was not delayed, increasing the delay to delivery of the larger reinforcer decreased the percentage of trials in which that reinforcer was chosen. All subjects directed the majority of choice responses to the smaller reinforcer when the larger reinforcer was sufficiently delayed, although the value at which this occurred differed across subjects. Under conditions in which the larger reinforcer initially was sufficiently delayed to result in preference for the smaller one, progressively increasing in 5-s increments the delay to both reinforcers increased percentage of trials with the larger reinforcer chosen. At sufficiently long delays, 2 of the subjects consistently chose the larger, but more delayed, reinforcer, and the 3rd subject chose that reinforcer on half of the trials. These results are consistent with the findings of prior studies in which adult humans responded to terminate noise and pigeons responded to produce food.  相似文献   
12.
A cost-benefit analysis of demand for food.   总被引:20,自引:17,他引:3       下载免费PDF全文
Laboratory studies of consumer demand theory require assumptions regarding the definition of price in the absence of a medium of exchange (money). In this study we test the proposition that the fundamental dimension of price is a cost-benefit ratio expressed as the effort expended per unit of food value consumed. Using rats as subjects, we tested the generality of this "unit price" concept by varying four dimensions of price: fixed-ratio schedule, number of food pellets per fixed-ratio completion, probability of reinforcement, and response lever weight or effort. Two levels of the last three factors were combined in a 2 x 2 x 2 design giving eight groups. Each group was studied under a series of six FR schedules. Using the nominal values of all factors to determine unit price, we found that grams of food consumed plotted as a function of unit price followed a single demand curve. Similarly, total work output (responses x effort) conformed to a single function when plotted in terms of unit price. These observations provided a template for interpreting the effects of biological factors, such as brain lesions or drugs, that might alter the cost-benefit ratio.  相似文献   
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14.
There appears to be a strong relationship between mass media portrayals of violence and real-life violence itself. This article reviews the available literature on the effects of media treatment of sports violence; analyzes the theoretical explanations for this treatment; and makes proposals on how the problems of both sports violence and its media coverage may be remedied, with a particular focus on amateur hockey in Canada.  相似文献   
15.
The belief is widely held that humor is related to recovery from, and perhaps an increased resistance to, coronary and other stress-related diseases. Such generalizations do not typically distinguish between benign and hostile humor. In the present research, the relationship between a measure of proneness to coronary heart disease (CHD) and appreciation of hostile and nonhostile humor is examined. In two studies, one with college students and one with patients suffering from CHD, the relationship between humor preferences and the coronary-prone (Type A) behavior pattern was examined. Each subject was given the Jenkins Activity Survey as a measure of the coronary-prone personality type, and aggressive and nonaggressive jokes to rate for funniness. Hostile humor was preferred to nonhostile humor by all groups, but among those suffering from CHD, those who could be classified as “Type B’s” preferred nonhostile humor. The results indicate that those less prone to CHD appreciate both hostile and nonhostile humor, while Type A’s seem to enjoy hostile humor only.  相似文献   
16.
Psychological symptoms were found to be associated with a number of cognitive appraisal and demographic variables but predicted primarily by perceived lack of control among information seekers in the aftermath of the Three Mile Island accident. Cognitive appraisal variables were found to be interrelated in a way which suggests that appraisal of control and faith in experts mediate between perceived environmental threat and psychological symptoms among information seekers in the aftermath of technological disaster. Demographic variables such as education and evacuation status are viewed as mediators between environmental circumstances and cognitive appraisals.  相似文献   
17.
The prevalence of regular smoking increases rapidly during adolescence. We applied modeling methods from the study of epidemic infectious disease to smoking behavior. Our "epidemic" models dealt with the process of transition among four states: nonsmoker (susceptible), trier (exposed), regular smoker (infected), and ex-smoker (recovered). The best fitting model was one in which the transition from nonsmoker to trier was a social contagion process where nonsmokers contacted either triers or regular smokers. All other transitions were treated as constant rate processes in which a constant proportion of eligible individuals made the transition in a given year. The recursive equation model embodying these assumptions was able to predict accurately the proportion of adolescents in each state in Grades 6–11. Our results support a "stage" model of smoking, suggesting that different psychological and physiological processes are involved in the initiation of smoking than in developing a habit of regular smoking. A possible sex difference was found in the non-contact transition between trier and smoker states, with the transition being more probable in females than in males.  相似文献   
18.
Affect, personality, and social activity.   总被引:3,自引:0,他引:3  
These studies examined relations between social activity and state and trait measures of Positive and Negative Affect. In Study 1 Ss completed scales relevant to 3-factor models of personality and a weekly mood and social activity questionnaire for 13 weeks. In Study 2 Ss completed measures of the 5-factor model of personality and a daily mood and social activity survey for 6-7 weeks. In within- and between-Ss analyses, socializing correlated significantly with state measures of Positive Affect and with trait measures of Extraversion/Positive Emotionality. These relations were relatively general across various types of positive affect and social events; however, specific types of social events also were differentially related to affect. In contrast, social activity had no consistent association with measures of Negative Affect or the other personality dimensions. The results support a temperamental view of Extraversion.  相似文献   
19.
Nine men participated in two experiments to determine the effects of increased response requirement and alcohol administration on free-operant aggressive responding. Two response buttons (A and B) were available. Pressing Button A was maintained by a fixed-ratio 100 schedule of point presentation. Subjects were instructed that completion of each fixed-ratio 10 on Button B resulted in the subtraction of a point from a fictitious second subject. Button B presses were defined as aggressive because they ostensibly resulted in the presentation of an aversive stimulus to another person. Aggressive responses were engendered by a random-time schedule of point loss and were maintained by initiation of intervals free of point loss. Instructions attributed these point losses to Button B presses of the fictitious other subject. In Experiment 1, increasing the ratio requirement on Button B decreased the number of ratios completed in 4 of 5 subjects. In Experiment 2, the effects of placebo and three alcohol doses (0.125, 0.25, and 0.375 g/kg) were determined when Button B presses were maintained at ratio values of 20, 40 and 80. Three subjects who reduced aggressive responding with increasing fixed-ratio values reduced aggressive responding further at higher alcohol doses. One subject who did not reduce aggressive responding with increasing fixed-ratio values increased aggressive responding at the highest alcohol dose. The results of this study support suggestions that alcohol alters aggressive behavior by reducing the control of competing contingencies.  相似文献   
20.
In a discrete-trials procedure with pigeons, a response on a green key led to a 4-s delay (during which green houselights were lit) and then a reinforcer might or might not be delivered. A response on a red key led to a delay of adjustable duration (during which red houselights were lit) and then a certain reinforcer. The delay was adjusted so as to estimate an indifference point--a duration for which the two alternatives were equally preferred. Once the green key was chosen, a subject had to continue to respond on the green key until a reinforcer was delivered. Each response on the green key, plus the 4-s delay that followed every response, was called one "link" of the green-key schedule. Subjects showed much greater preference for the green key when the number of links before reinforcement was variable (averaging four) than when it was fixed (always exactly four). These findings are consistent with the view that probabilistic reinforcers are analogous to reinforcers delivered after variable delays. When successive links were separated by 4-s or 8-s "interlink intervals" with white houselights, preference for the probabilistic alternative decreased somewhat for 2 subjects but was unaffected for the other 2 subjects. When the interlink intervals had the same green houselights that were present during the 4-s delays, preference for the green key decreased substantially for all subjects. These results provided mixed support for the view that preference for a probabilistic reinforcer is inversely related to the duration of conditioned reinforcers that precede the delivery of food.  相似文献   
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