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851.
A resistive shocking surface and an appropriate power supply are described. The efficacy of the system is illustrated with some data on the activity of pigeons and rats as a function of the voltage applied. 相似文献
852.
This paper considers the problem of timing events in computer-controlled experiments. A digital clock is defined as a time-mark generator or “ticker” and a counter. A discussion of time-mark generators commonly used in computers is followed by a consideration of several ways in which computer clocks are implemented and used. A framework for the latter discussion is provided by a classification of clocks in terms of whether the ticker or the counter (either or both) is internal or external to the computer. 相似文献
853.
A device for rapid recording of positioning responses is described. It utilizes an extremely simple, low-cost position transducer and two digital voltmeters or their equivalent. The device has the advantages of rapid, accurate measurement, reliability, ease of reading, and the potential for automatic recording of positional data in two dimensions. 相似文献
854.
Rats were trained on a two-response timing procedure which required that response B follow response A by at least a minimum specified interval in order to be reinforced with food. Repeated presentation (5 min on, 5 min off) of an auditory warning stimulus terminated by a brief electric shock to the feet (conditioned fear) produced a marked suppression in the frequency of A-to-B response sequences during the warning stimulus. The distribution of A-to-B interresponse times (timing behavior), however, did not change during the warning stimulus. 相似文献
855.
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857.
John R. Hills Marilyn B. Gladney Joseph A. Klock 《Journal of counseling and development : JCD》1967,45(7):640-647
The misgivings of college faculty, college administrators, and high school counselors about selective admissions are focused on 9 issues. Data relevant to those issues reveal that: (1) prediction of grades is sufficiently accurate to be useful; (2) prediction equations from one year are sound for use in the immediately succeeding years; (3) predictions of first-year grades are related to performance over the 2-year period at a junior college and the 4-year career at a senior college; (4) there may need to be separate prediction procedures for widely different majors, such as science and nonscience; (5) accurate predictions can be made before the student has completed high school; (6) the nonacademic courses students take do not reduce prediction accuracy; (7) introduction of selectivity has not been found to decrease diversity in educational opportunity; (8) grading practices in an institution will tend to fluctuate with the degree of selectivity; and (9) procedures are available to set admissions cutoffs, to provide students with sound counseling information, and to provide a second chance for those who do net meet minimum admissions standards. 相似文献
858.
16 factors dealing with motivation on the job were presented in a paired comparison format to 513 underprivileged adults in a federally supported job retraining project in South Carolina. They were directed to select for each pair the one factor which was more important to them on a job. Analyses were computed for the total sample and for subsamples based on race, sex, and economic environment of residence. The results point out that intrinsic, personal factors are more important than job context factors. Slight differences were found across sex; larger differences were found across race and economic environment. 相似文献
859.
Joseph C. Stevens 《Attention, perception & psychophysics》1967,2(5):189-192
The amount by which the apparent brightness of a visual field is inhibited by a surrounding field depends on the area of the inhibiting field. Interocular brightness matches showed that, as the size of a surrounding annulus is increased from a thin ring, the degree of inhibition on the brightness of an inner disk increases rapidly at first and then more slowly as the effect approaches an asymptote. The increase of the inhibition with size of annulus can be expressed as an increase in the exponent of the power function that relates the apparent brightness of the dish to its physical luminance. 相似文献
860.
The experimental design considered in this paper is one in which each of a group of several subjects is observed in the presence of each of the other subjects of the group, the entire set of possible pairings being repeated or replicated on several occasions. Analysis of variance formulas are described for this somewhat unusual design. Both the model of constants and mixed model are considered. Reliability formulas growing out of the analysis of variance calculations are developed.This work was supported in part by grants M-627; M-627C from the National Institutes of Health, Public Health Service. 相似文献