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121.
We apply the 'patchwork engine' (PE; van Tonder and Ejima, 2000 Neural Networks forthcoming) to encode spaces between textons in an attempt to find a suitable feature representation of anti-textons [Williams and Julesz, 1991, in Neural Networks for Perception volume 1: Human and Machine Perception Ed. H Wechsler (San Diego, CA: Academic Press); 1992, Proceedings of the National Academy of Sciences of the USA 89 6531-6534]. With computed anti-textons it is possible to show that tessellation and distribution of anti-textons can differ from that of textons depending on the ratio of texton size to anti-texton size. From this we hypothesise that variability of anti-textons can enhance texture segregation, and test our hypothesis in two psychophysical experiments. Texture segregation asymmetry is the topic of the first test. We found that targets on backgrounds with regular anti-textons segregate more strongly than on backgrounds with highly variable anti-textons. This neatly complements other explanations for texture segregation asymmetry (e.g. Rubenstein and Sagi, 1990 Journal of the Optical Society of America A 7 1632-1643). Second the relative significance of textons and anti-textons in human texture segregation is investigated for a limited set of texture patterns. Subjects consistently judged a combination of texton and anti-texton gradients as more conspicuous than texton-only gradients, and judged texton-only gradients as being more conspicuous than anti-texton-only gradients. In the absence of strong texton gradients the regularity versus irregularity of anti-textons agrees with perceived texture segregation. Using PE outputs as anti-texton features thus enabled the conception of various useful tests on texture segregation. The PE is originally intended as a general image segmentation method based on symmetry axes. With this paper we therefore hope to relate anti-textons with visual processing in a wider sense. 相似文献
122.
The current article suggests a possible synthesis of Skinner's (1957) treatment of verbal behavior with the more recent behavioral interpretation of language known as relational frame theory. The rationale for attempting to combine these two approaches is first outlined. Subsequently, each of the verbal operants described by Skinner is examined and subjected to a relational frame analysis. In each case, two types of operants are identified; one based on direct contingencies of reinforcement and the other based on arbitrarily applicable relational responding. The latter operants are labeled verbal because they can be distinguished from other forms of social behavior, and they appear to possess the symbolic or referential qualities often ascribed to human language. By applying relational frame theory to Skinner's verbal operants, we aim to contribute towards the development of a modern behavior-analytic research agenda in human language and cognition. 相似文献
123.
The measurement properties of the Center for Epidemiologic Studies--Depression Scale (CES-D; L. S. Radloff, 1977) were evaluated in a probability sample of homeless adults residing in a large and demographically diverse community. The findings from this investigation suggest that the CES-D is a reliable measure of depressive symptoms among homeless adults and that the factor structure of the scale replicates the factor structure found in the general population. Change in the CES-D scores was associated with change in residential status, with participants who had made a transition from homelessness to regular domicile, reporting significantly lower levels of depressive symptomatology. This result indicates the scale's sensitivity to current depressive mood, as affected by significant life events encountered by homeless persons. 相似文献
124.
This paper outlines the ways in which an individual’s notions of sexuality are challenged by immigration. It describes four basic facets of sexuality and the ways in which each are rooted in culture. These include (1) the relative importance of sexuality in daily life; (2) potential or overt homosexuality; (3) marriage—whether based on arrangement or love; and (4) cross-cultural romantic and marital relationships. Immigration can stir up conflicts in each of these realms and lead to defensive retreat into familiar customs or a counterphasic plunge into new cultural avenues. Ideally, it would lead to a working-through of these conflicts and subsequent growth in the immigrant’s understanding of his or her sexual self. 相似文献
125.
The effects of universal pre-K on cognitive development 总被引:2,自引:0,他引:2
In this study of Oklahoma's universal pre-K program, the authors relied on a strict birthday eligibility criterion to compare "young" kindergarten children who just completed pre-K to "old" pre-K children just beginning pre-K. This regression-discontinuity design reduces the threat of selection bias. Their sample consisted of 1,567 pre-K children and 1,461 kindergarten children who had just completed pre-K. The authors estimated the impact of the pre-K treatment on Woodcock-Johnson Achievement test scores. The authors found test impacts of 3.00 points (0.79 of the standard deviation for the control group) for the Letter-Word Identification score, 1.86 points (0.64 of the standard deviation of the control group) for the Spelling score, and 1.94 points (0.38 of the standard deviation of the control group) for the Applied Problems score. Hispanic, Black, White, and Native American children all benefit from the program, as do children in diverse income brackets, as measured by school lunch eligibility status. The authors conclude that Oklahoma's universal pre-K program has succeeded in enhancing the school readiness of a diverse group of children. 相似文献
126.
This article examines how between-individual comparisons influence performance evaluations in rating tasks. The authors demonstrated a systematic change in the perceived difference across ratees as a result of changing the way performance information is expressed. Study 1 found that perceived performance difference between 2 individuals was greater when their objective performance levels were presented with small numbers (e.g., absence rates of 2% vs. 5%) than when they were presented with large numbers (e.g., attendance rates of 98% vs. 95%). Extending this finding to situations involving trade-offs between multiple performance attributes across ratees, Study 2 showed that the relative preference for 1 ratee over another actually reversed when the presentation format of the performance information changed. The authors draw upon prospect theory to offer a theoretical framework describing the between-individual comparison aspect of performance evaluation. 相似文献
127.
When moderation is mediated and mediation is moderated 总被引:17,自引:0,他引:17
Procedures for examining whether treatment effects on an outcome are mediated and/or moderated have been well developed and are routinely applied. The mediation question focuses on the intervening mechanism that produces the treatment effect. The moderation question focuses on factors that affect the magnitude of the treatment effect. It is important to note that these two processes may be combined in informative ways, such that moderation is mediated or mediation is moderated. Although some prior literature has discussed these possibilities, their exact definitions and analytic procedures have not been completely articulated. The purpose of this article is to define precisely both mediated moderation and moderated mediation and provide analytic strategies for assessing each. 相似文献
128.
de Greef MH Sprenger SR Elzenga CT Popkema DY Bennekers JH Niemeijer MG Middel B Mook GA 《Perceptual and motor skills》2005,100(2):567-575
This study examined the reliability and validity of a 12-min. walking test for coronary heart disease patients. CHD patients (28 men, 18 women) were recruited out of 86 CHD patients of the Martini Hospital Groningen, The Netherlands. 46 CHD patients (age M=66.0 yr., SD=6.8) participated in the reliability study and 24 (age M=62.0 yr., SD=9.2) in the validity study. A test-retest analysis showed a satisfactory Bland-Altman plot and an intraclass coefficient of .98. The Pearson correlation between the score on the test and the VO2 peak was .77. This test gives a reliable and valid assessment of cardiorespiratory fitness of CHD patients. 相似文献
129.
The original Kirton Adaption-Innovation Inventory, used to measure innovative (as opposed to adaptive) individual cognitive styles, has been reported to have three factors: Sufficiency of Originality, Efficiency, and Rule/Group Conformity. In exploring the construct validity of the Kirton Adaption-Innovation Inventory, findings from a 2003 study by Im, Hu, and Toh showed the existence of two subdimensions of the Sufficiency of Originality factor-Idea Generation and Preference for Change. In this study, using a sample of 356 household participants, with an average age of 56.0 yr. (SD = 14.0), average income of dollar 39,700 (SD = dollar 19,200), and average of 15.0 yr. of education (SD = 2), from the Arkansas Household Research Panel, we conducted factor analyses. The results specific to our selected sample indicate that a four-factor model recognizing the two subdimensions of Sufficiency of Originality has a better fit than the original three-factor model. 相似文献
130.
This study aimed to examine the effects of directing attention to the spatial dimension of the circle-drawing task on interlimb coordination patterns across limbs. Eighteen participants performed a circle-drawing task involving in-phase and antiphase coordination modes under upper limb, contralateral and ipsilateral limb combinations. Results indicated that (a) coordination pattern stability co-varied with central cost when attentional focus was directed to the spatial dimensions of the interlimb circle-drawing task; (b) attentional focus on the spatial components modified the inherent performance asymmetries between the limbs; (c) finally, attention to the spatial components of the interlimb circle-drawing task modulated movement trajectories and at the same time the stability of temporal coordination. 相似文献