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841.
Relative allocation on concurrent schedules can depend on schedule parameters when behavioral parameters are constant 总被引:1,自引:1,他引:0
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Houston AI McNamara JM Sumida BH 《Journal of the experimental analysis of behavior》1987,47(1):127-131
We develop a simple model of switching between the initial links of a concurrent-chain procedure. Behavior is determined by four parameters μ1, μ2, q1, and q2. The first two are the basic rates of switching from Schedule 1 and Schedule 2, respectively. The second two are the probabilities of leaving Schedule 1 and Schedule 2 after the corresponding terminal link has been completed. We show that for fixed values of these four parameters, the relative allocation on the initial links may change as a result of changes in initial-link schedules. The effect can be quite large if the switching rates are low. An implication is that relative allocation is not necessarily a good measure of behavior. 相似文献
842.
Pigeons' responses were reinforced on a variant of a mixed variable-interval extinction schedule of reinforcement in which the transition to the higher reinforcement rate was signaled by a trace stimulus projected on the response key prior to the onset of the component correlated with food delivery. In the first of two experiments, the duration of the trace stimulus preceding the component correlated with food delivery was varied from 1.5 to 50.0 s and in the second experiment, the reinforcement frequency in the same component was varied from 10 to 60 reinforcers per hour. Pigeons pecked at the trace stimulus preceding the onset of the component correlated with food delivery even though responding was not reinforced in its presence and only one of the changes in reinforcement rate (i.e., from extinction to reinforcement) was signaled. The rate of pecking during the trace stimulus was a function of its duration but not of the reinforcement frequency in the following component. Higher rates generally occurred at the shorter trace-stimulus durations. Component responding following the offset of the trace stimulus was under discriminative control of the trace stimulus whether or not responding occurred in the presence of the trace stimulus. 相似文献
843.
McIntire KD Cleary J Thompson T 《Journal of the experimental analysis of behavior》1987,47(3):279-285
Two cynomolgous macaques categorized six colors into two groups of three after conditional discrimination training (zero-delay symbolic match-to-sample). The procedures resulted in the establishment of relations among the elements of each set-relations that were not specifically trained and that can be characterized by the properties of reflexivity, symmetry, and transitivity. Each set of colors was related to a characteristic pattern of responding: One response pattern involved temporal duration (press and hold the response keys); the second response pattern entailed repeated pressing and releasing of the response keys (fixed ratio 8). Six combinations of two colors were trained, three combinations from each set. After discriminative performance stabilized for each monkey, they were tested with 10 additional color combinations, all of which differed from the training combinations. The conditional relations established between test combinations can be characterized as stimulus equivalence. The training procedures were analogous to the procedure of using category names, and have implications for understanding the function of language in the formation of equivalence classes. 相似文献
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