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911.
A. John Ernst Larry Engberg David R. Thomas 《Journal of the experimental analysis of behavior》1971,16(2):177-180
Twelve pigeons were given successive discrimination training involving variable-interval reinforcement for key pecking in the presence of one intensity of monochromatic light randomly alternated with extinction for pecking during another intensity. All of the pigeons were then tested in extinction for generalization along the intensity dimension, and all showed a displacement of maximal responding from the positive stimulus in the direction opposite the negative stimulus. For six of the pigeons, for which the test included only three values beyond the positive stimulus, four showed peaked gradients but two did not, showing monotonic gradients with maximal responding to the most extreme test value. For another six pigeons tested over a wider range, all showed peaked gradients. Thus, when a sufficiently wide range of test values is employed, generalization gradients for visual intensity have the same peaked form as do gradients for qualitative visual dimensions such as wavelength or line angle. 相似文献
912.
913.
914.
Warning responses are described on the basis of interviews with 278 randomly selected families who were evacuated from their homes prior to a flood in Denver, Colorado, on June 16, 1965. Response patterns are analyzed in detail for families who were geographically separated at the time initial warnings were received. Numerous implications for community disaster planning are explicated. 相似文献
915.
An inexpensive way to produce continuous variation in the luminance of a computer-controlled CRT display is described. One application of that system to the study of motion-analyzers in human vision is discussed briefly. 相似文献
916.
Milton D. Hakel Thomas D. Hollmann Marvin D. Dunnette 《Journal of counseling and development : JCD》1968,46(8):762-764
Forty-two years ago, Counts (1925) surveyed the social status of occupations and found a well-defined prestige order, with banker at the top and ditch digger at the bottom. Because of changes wrought by the depression and World War II, Deeg and Paterson (1947) repeated Counts' study and found only minor relative changes in social status. Because of the extensive social and cultural changes since World War II, Counts' study was repeated again, and again only minor relative changes in the social status of occupations were found. The prestige order of the occupations surveyed is remarkably stable. 相似文献
917.
John R. Thomas 《Journal of the experimental analysis of behavior》1968,11(5):609-616
Pigeons' responding was maintained by two concurrently available variable-interval reinforcement schedules. A fixed-ratio punishment schedule of timeout periods from the concurrent reinforcement schedules was arranged for responding during one of the variable-interval schedules. The greater the probability of a timeout after a response on the punished variable-interval schedule (the smaller the fixed ratio that produced timeout), the greater the decline in the relative punished response rates. Relative reinforcement rates remained invariant when relative response rates declined. Both behavioral contrast and induction effects were observed on the unpunished variable-interval schedule as a function of timeout punishment of the other schedule. 相似文献
918.
The five pigeons in Group 1 were given successive intradimensional discrimination training in which responses to a line of 49 degrees were reinforced on a variable-interval schedule and responses to a line of 33 degrees were not reinforced. Subsequent generalization testing with other line orientations revealed a peak shift from the positive stimulus in the direction away from the negative stimulus in all subjects. The four pigeons in Group 2 received successive discrimination training with the 49 degrees value on the key during both stimuli. During the negative stimulus, however, the floor was tilted 16 degrees counterclockwise. When tested (with the floor flat) these subjects showed peak shifts similar to those observed with Group 1. A third group of three pigeons, given successive interdimensional discrimination training with the 49 degrees line as the positive stimulus and the absence of the line as the negative, showed no peak shift in a subsequent generalization test. It was concluded that tilting the floor on which the pigeon stood systematically distorted the bird's visual perception of the orientation of the line in a manner consistent with the results of other studies in this laboratory. 相似文献
919.
F. Thomas Cloar Kenneth B. Melvin 《Journal of the experimental analysis of behavior》1968,11(2):187-190
Two bobwhite quail (Colinus virginianus) and two Japanese quail (Coturnix coturnix japonica) were trained to peck a response key to obtain food. In general, performance on fixed ratio 20 and variable- and fixed-interval 60-sec schedules was comparable to the response patterns of other species under these schedules. 相似文献
920.
An attempt was made to vary systematically the behavior of two elementary school teachers to determine the effects on classroom behavior of Rules, Ignoring Inappropriate Behaviors, and showing Approval for Appropriate Behavior. Behaviors of two children in one class and one child in the other class were recorded by observers, as were samples of the teachers' behavior. Following baseline recordings, Rules, Ignoring, and Approval conditions were introduced one at a time. In one class a reversal of conditions was carried out. The main conclusions were that: (a) Rules alone exerted little effect on classroom behavior, (b) Ignoring Inappropriate Behavior and showing Approval for Appropriate Behavior (in combination) were very effective in achieving better classroom behavior, and (c) showing Approval for Appropriate Behaviors is probably the key to effective classroom management. 相似文献