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251.
D LaBerge V Brown M Carter D Bash A Hartley 《Journal of experimental psychology. Human perception and performance》1991,17(1):65-76
Three experiments explored the gradual narrowing of visual attention to a letter target when other letters were positioned close by. The method by which attention was narrowed involved presenting a digit target immediately prior to the latter target and in the same location for progressively shorter durations and requiring the subject to identify both the digit target and the letter target before responding. The response time data from the first 2 experiments indicated that shorter durations of the digit reduced the amount of information processed from noise letters positioned on either side of the letter target. In the third experiment, in which separation of letters was increased slightly, the response times indicated that the information from flanking noise letters may have been virtually eliminated. 相似文献
252.
I M Pepperberg M V Brezinsky 《Journal of comparative psychology (Washington, D.C. : 1983)》1991,105(3):286-294
We report that an African gray parrot (Psittacus erithacus), Alex, responds to stimuli on a relative basis. Previous laboratory studies with artificial stimuli (such as pure tones) suggest that birds make relational responses as a secondary strategy, only after they have acquired information about the absolute values of the stimuli. Alex, however, after learning to respond to a small set of exemplars on the basis of relative size, transferred this behavior to novel situations that did not provide specific information about the absolute values of the stimuli. He responded to vocal questions about which was the larger or smaller exemplar by vocally labeling its color or material, and he responded "none" if the exemplars did not differ in size. His overall accuracy was 78.7%. 相似文献
253.
Although a wide variety of factors have been found to be related to health in some way, researchers on the subject of health generally fail to integrate findings of other research disciplines within their own line of research. This study has attempted to bring together two research disciplines: (a) research on personality and health, and (b) research on socio-economical differences in health. Personality factors as well as social class have been found to mediate the stress-illness relation. Based on empirical and theoretical considerations, we proposed a simple model for the occurrence and course of disease. The personality factors studied were neuroticism, locus of control, and self-esteem. Socio-economic status (SES) was represented by education level, occupation status, and income. Health was operationalized as the number of somatic diseases. The research questions were investigated (using t-tests andpath analysis) in a longitudinal set of data that were collected between 1970 and 1984 among 245 subjects in the normal population. Neuroticism appeared to be an important mediator of the stress-illness relation. Of the SES variables, occupation and education served as mediators; education was especially infuential on the course of disease. The role of neuroticism is discussed. 相似文献
254.
Decomposition is a common strategy for dealing with the complexity of multiattribute decision problems. A cognitively demanding task is broken down into tasks requiring simpler, perhaps easier, judgments which can then be aggregated. But individual judgments can be inconsistent in systematic or random fashion and when aggregated there is the possibility of propagation of this inconsistency. In this paper inconsistency in the form of random error is investigated in the context of additive decomposition of multiattribute utility. The process of aggregation of random error is studied and a comparison made with random error in holistic estimates of multiattribute utility. Conditions under which decomposition improves the consistency of the multiattribute utility estimate are presented and discussed. 相似文献
255.
MULTIDIMENSIONAL SCALING OF LARGE CHROMATIC DIFFERENCES BY NORMAL AND COLOR-DEFICIENT SUBJECTS 总被引:1,自引:0,他引:1
The following two articles offer a glimpse at current experimental psychology in the Soviet Union, normally screened from the English-speaking world by all but impenetrable language barriers. The accompanying Commentary by Tarow Indow helps place these contributions in the framework of contemporary work on the psychophysics of color perception. Abstract —
Fifteen normal trichromatic subjects, two protanopes, and two deuteranopes judged pairs of successively presented foveal color stimuli. Multidimensional scaling of the data yielded estimates of a three-dimensional space with axes interpreted as red–green, blue-yellow, and white-black. For color-deficient subjects, the average radius of the space differed from that of normals, being smaller for the protanopes and larger for the deuteranopes. For both types of color deficiency, the blue-yellow axis was stretched relative to the red-green, more strongly in the protanopes. The findings are taken to support the generality of a "spherical" model. 相似文献
Fifteen normal trichromatic subjects, two protanopes, and two deuteranopes judged pairs of successively presented foveal color stimuli. Multidimensional scaling of the data yielded estimates of a three-dimensional space with axes interpreted as red–green, blue-yellow, and white-black. For color-deficient subjects, the average radius of the space differed from that of normals, being smaller for the protanopes and larger for the deuteranopes. For both types of color deficiency, the blue-yellow axis was stretched relative to the red-green, more strongly in the protanopes. The findings are taken to support the generality of a "spherical" model. 相似文献
256.
William P. Hetrick Robert C. Isenhart Derek V. Taylor Curt A. Sandman 《Behavior research methods》1991,23(1):66-71
A software program written to collect real-time, observational data is described. The flexible program allows customized behavior codes and observational durations and simultaneously records both timed and counted events. The data are collected by means of single keystrokes, automatically stored to disk with 100th of a second resolution and summarized for each observational session. The program’s database files are dBASE III PLUS compatible and may be browsed, edited, or converted to ASCII files from the program’s main menu. Field testing demonstrated the efficiency and interobserver reliability of the program (for frequency,r=0.81; for durational behaviors,rs=0.89 and 0.96). The software operates on IBM XT/AT/PS 2s and most clones with PC/MS DOS version 2.0 or greater. 相似文献
257.
We present a class of stimuli that makes it possible to study the interaction of visual attributes in forming textural patterns. These stimuli are obtained in a simple manner from a class of motion stimuli that we described earlier (Papathomas & Gorea, 1988). The main advantages of the texture stimuli presented in this paper are: (1) each attribute can be arranged simultaneously with, but independently of, other attributes, (2) an arbitrary number of attributes can be used, (3) the interaction of attributes can be studied systematically, (4) direct comparison of two attributes is possible with stimuli in which the two are arranged to form competing patterns, and (5) because of the similarity to the motion stimuli, the relationship between texture and motion mechanisms can be investigated. 相似文献
258.
259.
Performance of humans in concurrent avoidance/positive-reinforcement schedules 总被引:1,自引:1,他引:0 下载免费PDF全文
Ruddle HV Bradshaw CM Szabadi E Foster TM 《Journal of the experimental analysis of behavior》1982,38(1):51-61
Performance maintained under concurrent schedules consisting of a variable-interval avoidance component and a variable-interval positive-reinforcement component was studied in three human subjects using points exchangeable for money as the reinforcer. The rate of responding in the avoidance component increased, and the rate of responding in the positive-reinforcement component declined, as a function of the frequency of point-losses avoided in the avoidance component. The performance of all three subjects conformed to equations proposed by Herrnstein to describe behavior in concurrent schedules. The logarithms of the ratios of the response rates in the two components, and the logarithms of the ratios of the times spent in the two components, were linearly related to the logarithms of the ratios of the frequency of loss avoidance in the avoidance component to the frequency of reinforcement in the positive-reinforcement component. When a changeover delay of 5.0 sec was imposed, the slopes of the linear functions were close to 1.0 in the case of two subjects, whereas the third subject exhibited significant undermatching. For two subjects the changeover delay was then reduced to 2.0 sec; in both cases the slopes of the linear functions were lower than under the 5.0-sec condition. One subject participated in a third phase, in which no changeover delay was imposed; there was a further reduction in the slopes of the linear functions. 相似文献
260.
How do we use place information in a number comparison task involving multidigit numbers? In four experiments, subjects identified stimulus numbers as larger or smaller than the number 5,000 in a choice reaction time task. As the difference between the number of places in the stimulus number and the number of places in the standard decreased, response time and errors significantly increased. When the number of places was held constant, the type of numeric information extracted depended on the value of the standard (5,000 or 5,555). In some cases, irrelevant place information affected choice time. 相似文献