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11.
S R Hursh T G Raslear D Shurtleff R Bauman L Simmons 《Journal of the experimental analysis of behavior》1988,50(3):419-440
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
12.
Perception of translational heading from optical flow 总被引:3,自引:0,他引:3
W H Warren M W Morris M Kalish 《Journal of experimental psychology. Human perception and performance》1988,14(4):646-660
Radial patterns of optical flow produced by observer translation could be used to perceive the direction of self-movement during locomotion, and a number of formal analyses of such patterns have recently appeared. However, there is comparatively little empirical research on the perception of heading from optical flow, and what data there are indicate surprisingly poor performance, with heading errors on the order of 5 degrees-10 degrees. We examined heading judgments during translation parallel, perpendicular, and at oblique angles to a random-dot plane, varying observer speed and dot density. Using a discrimination task, we found that heading accuracy improved by an order of magnitude, with 75%-correct thresholds of 0.66 degrees in the highest speed and density condition and 1.2 degrees generally. Performance remained high with displays of 63-10 dots, but it dropped significantly with only 2 dots; there was no consistent speed effect and no effect of angle of approach to the surface. The results are inconsistent with theories based on the local focus of outflow, local motion parallax, multiple fixations, differential motion parallax, and the local maximum of divergence. But they are consistent with Gibson's (1950) original global radial outflow hypothesis for perception of heading during translation. 相似文献
13.
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
14.
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
15.
Warren Shibles 《Argumentation》1988,2(1):99-115
The traditional and prevailing definition of lying is that lying is some variation or combination of: an untruth told with intent to deceive. I establish that this is the case, and that, as a result, contradictions and injustices arise. An alternative definition is proposed which is shown to avoid these difficulties. It is also shown that and how on the new definition the alleged Liar paradox is easily dissolved. 相似文献
16.
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
17.
Choice with delayed and probabilistic reinforcers: effects of variability, time between trials, and conditioned reinforcers. 下载免费PDF全文
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
18.
Three experiments were performed to examine the role that central and peripheral vision play in the perception of the direction of translational self-motion, or heading, from optical flow. When the focus of radial outflow was in central vision, heading accuracy was slightly higher with central circular displays (10 degrees-25 degrees diameter) than with peripheral annular displays (40 degrees diameter), indicating that central vision is somewhat more sensitive to this information. Performance dropped rapidly as the eccentricity of the focus of outflow increased, indicating that the periphery does not accurately extract radial flow patterns. Together with recent research on vection and postural adjustments, these results contradict the peripheral dominance hypothesis that peripheral vision is specialized for perception of self-motion. We propose a functional sensitivity hypothesis--that self-motion is perceived on the basis of optical information rather than the retinal locus of stimulation, but that central and peripheral vision are differentially sensitive to the information characteristic of each retinal region. 相似文献
19.
Much of the methodology in stress research focuses on stress manifestation and organismic reactions to life’s crises. In contrast,
the present study sought to identify the major sources of stress and the nature of those sources. The results revealed a consistent
pattern in high and low stressors throughout the 3-year period of the study, and differences only of intensity between males
and females, not type of stress. Except for individuals’ temporal variations in critical events, the highest stressors for
the groups were external, primarily financial and time management. Internal sources, such as personal relationships and self-absorption,
were typically the lowest concerns. Everyday problems arising from current life styles seem to be significant sources of stress. 相似文献
20.
Two experiments are reported which investigated how subject gender and time-of-day influenced the estimation of duration and
the perception of task-related mental workload. In the first experiment, 24 subjects performed a filled time-estimation task
in a constant blacked-out, noise-reduced environment at 0800h, 1200h, 1600h, and 2000h, respectively. In the second experiment,
12 different subjects performed an unfilled time estimation task in similar conditions at 0900h, 1400h, and 1900h. At the
termination of all experimental sessions, participants completed the NASA Task Load Index workload assessment questionnaire
as a measure of perceived mental workload. Results indicated that physiological response, reflected in body temperature change,
followed an expected pattern of sequential increase with time-of-day. However, estimates of duration and the perception of
mental workload showed no significant effects for time-of-day. In each of the experiments there were significant differences
in time estimation and mental workload response contingent on the gender of the participant. These results are interpreted
in light of the previous positive findings for circadian fluctuation in performance efficiency and the equivocal findings
of a gender difference in time estimation. A unifying account of these collective results is given based on gender by time-of-day
interactional effects.
An earlier version of this paper was presented at the 32nd Annual Meeting of the Human Factors Society, Anaheim, CA, October,
1988. 相似文献