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61.
Myron Charles Baker Diana F. Tomback Daniel B. Thompson Tad C. Theimer Dana C. Bradley 《Learning and motivation》1984,15(4):428-440
The functional significance of learned population differences in male song in the white-crowned sparrow was explored in natural populations using playback tests. Laboratory results have shown that learning of the population-specific song seems to take place in early life and is strongly dependent upon the nature of the auditory experience at that time. However, the varied results of recent studies make it difficult to reach a confident conclusion about the ecological functions of song learning. The present research took advantage of naturally occurring variation in the differences between songs of adjacent populations to determine a function relating degree of difference in song to intensity of territorial singing elicited. Applying a typological evaluation of syllable structure to the four segments of the song allowed a crude quantitative ranking of the differences between local songs and playback stimuli. These results, together with those of other studies, suggest a unimodal aggressive response function of males to songs of other males. A maximum response to songs slightly different from the local song environment suggests that male exclusion based upon acquired song components may contribute to the maintenance of discrete and stable song dialects. 相似文献
62.
Harvey Charles Peters Bagmi Das Mina Attia Maggie M. Parker 《Journal of Employment Counseling》2023,60(1):2-16
Higher education faculty worldwide experienced heightened stressors due to the COVID-19 pandemic, from completing their professional roles and responsibilities virtually to balancing personal and professional stressors. Consequently, the pandemic created many adjustments for pre-tenure counseling faculty across research, teaching, and service. In response to this pandemic, we explored the impact of the COVID-19 pandemic on the personal and professional lives of four pre-tenure counseling faculty members. Accordingly, we used collaborative autoethnography to investigate our experiences and narratives as pre-tenure counseling faculty, which resulted in seven overarching themes. We discussed the implications for practice, advocacy, education, and faculty training. 相似文献
63.
Instead of using percent correct identifications or detections as the dependent variable, latency in voicing the target stimulus was measured in a backward masking paradigm. Reaction time (RT) to target letters was reliably increased when they were simultaneously encircled by a black ring mask of a size found to produce masking using an identification or detection criterion. The masking function in terms of RT was typical in shape, a decreasing function of stimulus onset asynchrony (SOA) over an interval of 150 msec. Since the target remained “on” when the mask appeared, the results are incompatible with an erasure interpretation of masking effects. Analyses of the variances of the RTs supported an interpretation of a progressive decrease in masking effects as SOA increased. 相似文献
64.
David S. Emmerich James L. Gray Charles S. Watson David C. Tanis 《Attention, perception & psychophysics》1972,11(1):65-72
Response latencies were obtained from 10 Ss in auditory signal-detection experiments. The response latencies were inversely related to certainty that a signal was (or was not) presented. The S’s decision criterion was found to have an influence on response latency, which was consistent with the hypothesis that stimuli close to the current criterion elicit longer response latencies than stimuli more distant from the criterion. Comparisons among receiver operating characteristics derived from binary decisions, from the latencies of binary decisions, and from confidence ratings show that response latencies and binary decisions together yield more information about the stimulus than does the binary decision alone. However, the increment in information gained from the measurement of response latencies is in general (though not for every S) smaller than that gained by shifting from yes-no responses to a confidence-rating procedure. 相似文献
65.
A circuit to permit an electronic drinkometer to operate during footshock is described. The circuit employs a diode matrix that allows all grid bars to be connected at one point to form one electrode of the drinkometer; it is isolated at another point so as not to shortcircuit the impressed footshock. 相似文献
66.
Measures of test parsimony and factor parsimony are defined. Minimizing their weighted sum produces a general rotation criterion
for either oblique or orthogonal rotation. The quartimax, varimax and equamax criteria are special cases of the expression.
Two new criteria are developed. One of these, the parsimax criterion, apparently gives excellent results. It is argued that
one of the most important factors bearing on the choice of a rotation criterion for a particular problem is the amount of
information available on the number of factors that should be rotated.
This research was supported by the National Research Council of Canada research grant 291-13 to Dr. G. A. Ferguson. 相似文献
67.
Pressurized air was repeatedly associated with one of two frequencies of flashing light during performance of a VI 30-sec positive reinforcement schedule by stump-tailed monkeys. As revealed by the relative suppression of bar presses to each of the two visual stimuli, the Ss learned to discriminate between the different flicker frequencies. However, they also showed signs of adapting to the airblast during the course of training, and its location had to be changed in order to maintain discriminative suppression. 相似文献
68.
The detection of luminance increments in a homogeneously lighted field was studied as a function of the area and perimeter of the luminance increment. Sixteen targets representing all possible combinations of four values of area and four values of perimeter were foveally presented. Exposure durations were short (25 to 40 msec). Results of both an analysis of variance and linear discriminant analysis indicated that detection probability increases as area increases, but neither variations in perimeter nor perimeter-area combinations produced effects that were significant oyer the experiment as a whole. The linear discriminant analysis revealed individual differences in the effects of perimeter and area on detection probability. Results were contradictory to Kristofferson’s (1957) “element contribution theory” and gave only slight support to Hecht’s (Lamar, Hecht, Shlaer, & Hendley, 1947) “border-quantum theory.” 相似文献
69.
70.
Superstitions were demonstrated with human subjects when presses on one button were reinforced on a VI 30-sec schedule while presses on a second were never reinforced. Superstitious responding, on the second button, was often maintained because presses on that button were frequently followed by reinforcement for a subsequent press on the first button. The introduction of a changeover delay (COD), which separated in time presses on the second button and subsequent reinforced presses on the first button, reduced or eliminated the superstitious responding of these subjects. Some complex superstitions were also demonstrated with other subjects for which the COD was in effect from the beginning of the session. 相似文献