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801.
An X Windows software tool for the construction of faces with a weighted combination of eigenvectors is described. The eigenvectors were extracted from an autoassociative matrix that comprised 100 face images. The program input consists of eigenvectors and sets of weights that describe individual faces and combines these to create face images. The tool creates a panel of buttons that permits the display of individual eigenvectors and the display of an average face as well. Facilities for on-line changes to the intensity of individual eigenvectors can be used to change the appearance of a face. Previously, O’Toole, Abdi, Deffenbacher, and Bartlett (1991) have shown that the intensity of certain individual eigenvectors contains reliable information for determining the sex and race of the face. 相似文献
802.
Commercial database programs such as dBase and Paradox, although developed originally for business applications, are versatile and powerful tools that can be used for an academic purpose such as evaluating student performance. They can be used to write and store test questions, assemble and print classroom or on-line laboratory tests, and calculate grades, test statistics, and so forth. Databases are flexible, unlike textbook “ancillary” test bank programs that are inextricably bound to the strictly linear format and brief shelf life of specific textbook editions. A prototypical relational database program is described, with which an instructor can produce tests based on generic terms adapted from Boneau’s (1990) study of psychological literacy, as well as on behavioral learning objectives adapted from Bloom’s (1956) taxonomy of educational objectives. As a relational database, the program integrates terms, objectives, questions, tests, and test scores, and avoids unnecessary data duplication and waste of computer storage space. 相似文献
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Sjoerd C. de Vries Astrid M. L. Kappers Jan J. Koenderink 《Attention, perception & psychophysics》1993,53(1):71-80
We used quadratic shapes in several psychophysical shape-from-stereo tasks. The shapes were elegantly represented in a 2-D parameter space by the scale-independentshape index and the scale-dependentcurvedness. Using random-dot stereograms to depict the surfaces, we found that the shape of hyperbolic surfaces is slightly more difficult to recognize than the shape of elliptic surfaces. We found that curvedness (and indirectly, scale) has little or no influence on shape recognition. 相似文献
805.
Frederick L. Kitterle Stephen Christman Jorge Conesa 《Attention, perception & psychophysics》1993,54(6):785-793
The relationship between local/global and high/low spatial-frequency processing in hemispheric asymmetries was explored. Subjects were required to judge the orientation of a high- or low-spatial-frequency component of a compound grating presented in the left visual field (LVF) or right visual field (RVF). In Experiment 1, attention was focused on one or the other component. A signal detection analysis indicated that sensitivity (d′) to the high-spatial-frequency target was reduced more by the presence of the low-spatial-frequency component when both were presented in the LVF rather than in the RVF. In Experiment 2, subjects determined whether a target orientation was present, independent of spatial frequency at only a single level (i.e., at the high- or low-spatial-frequency level), as opposed to both or neither level. An RVF/LH (left hemisphere) advantage was found when the decision was based on the orientation of the high-frequency component. The asymmetrical influence of visual field of presentation and spatial frequency upon sensitivity is discussed in terms of hemispheric differences in the magnitude of inhibition between spatial-frequency channels and in the role of transient channel activity to capture and direct higher order attentional processes. 相似文献
806.
The effects of distractor clustering on target detection were examined in two experiments in which subjects attended to binaural tone bursts of one frequency while ignoring distracting tones of two competing frequencies. The subjects pressed a button in response to occasional target tones of longer duration (Experiment 1) or increased loudness (Experiment 2). In evenly spaced conditions, attended and distractor frequencies differed by 6 and 12 semitones, respectively (e.g., 2096-Hz targets vs. 1482- and 1048-Hz distractors). In clustered conditions, distractor frequencies were grouped; attended tones differed from the distractors by 6 and 7 semitones, respectively (e.g., 2096-Hz targets vs. 1482- and 1400-Hz distractors). The tones were presented in randomized sequences at fixed or random stimulus onset asynchronies (SOAs). In both experiments, clustering of the unattended frequencies improved the detectability of targets and speeded target reaction times, Similar effects were found at fixed and variable SO As. Results from the analysis of stimulus sequence suggest that clustering improved performance primarily by reducing the interference caused by distractors that immediately preceded the target. 相似文献
807.
LEON SLOMAN M.D. F.R.C.P.. STEPHEN SPRINGER Ph.D. C.Psych. MARY L.S. VACHON R.N. Ph.D. 《Family process》1993,32(2):171-183
When a deaf child is born to hearing parents, a grieving process is initiated in the parents. Unresolved grieving over their child's deafness often makes it difficult for hearing parents to accept the importance of signing, thus increasing the child's problems — further source of grief for these parents. Clinical illustrations are provided of (1) the reciprocal relationship between disruption of the mourning process and disturbance of communication between family members, and (2) the transmission of the dysfunctional relationship between hearing parents and deaf children to the subsequent relationship between the deaf children, when they reach adulthood, and their hearing children. 相似文献
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