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1.
Correspondence analysis and optimal structural representations   总被引:1,自引:0,他引:1  
Many well-known measures for the comparison of distinct partitions of the same set ofn objects are based on the structure of class overlap presented in the form of a contingency table (e.g., Pearson's chi-square statistic, Rand's measure, or Goodman-Kruskal'sτ b ), but they all can be rephrased through the use of a simple cross-product index defined between the corresponding entries from twon ×n proximity matrices that provide particular a priori (numerical) codings of the within- and between-class relationships for each of the partitions. We consider the task of optimally constructing the proximity matrices characterizing the partitions (under suitable restriction) so as to maximize the cross-product measure, or equivalently, the Pearson correlation between their entries. The major result presented states that within the broad classes of matrices that are either symmetric, skew-symmetric, or completely arbitrary, optimal representations are already derivable from what is given by a simple one-dimensional correspondence analysis solution. Besides severely limiting the type of structures that might be of interest to consider for representing the proximity matrices, this result also implies that correspondence analysis beyond one dimension must always be justified from logical bases other than the optimization of a single correlational relationship between the matrices representing the two partitions.  相似文献   

2.
Harshman's DEDICOM model providesa framework for analyzing square but asymmetric materices of directional relationships amongn objects or persons in terms of a small number of components. One version of DEDICOM ignores the diagonal entries of the matrices. A straight-forward computational solution for this model is offered in the present paper. The solution can be interpreted as a generalized Minres procedure suitable for handing asymmetric matrices.  相似文献   

3.
The present paper describes a performance method for determining hand preference. The task requires participants to reach into different regions of hemispace to perform various actions (point, pick up, toss, sweep, and position) with a dowel located at each position. In accordance with the participants' hand preference as measured by the Waterloo Handedness Questionnaire, the preferred hand was used more frequently on the various performance tasks. The distribution of hand use in working space indicates that preferred hand use was almost exclusive for actions carried out in ipsilateral hemispace, while it is used only moderately for actions in contralateral hemispace, revealing that this hand is used throughout a wider range of extrapersonal space than the nonpreferred hand. These trends were observed across all of the performance tasks, suggesting that task complexity did not affect the frequency of preferred hand use either overall or, more specifically, in right hemispace, as was predicted. This finding is inconsistent with empirical work on questionnaires indicating that verbal reports of preferred hand use increase for more complex tasks (e.g., Steenhuis & Bryden, 1988). As well, performance on the preferential reaching task correlated significantly with hand preference as measured on the Waterloo Handedness Questionnaire (Bryden, 1977), unlike the other performance measure examined, indicating that the preferential reaching task is sensitive to differences in the degree of hand preference.  相似文献   

4.
Humans have a preference for curved over angular shapes, an effect noted by artists as well as scientists. It may be that people like smooth curves or that people dislike angles, or both. We investigated this phenomenon in four experiments. Using abstract shapes differing in type of contour (angular vs. curved) and complexity, Experiment 1 confirmed a preference for curvature not linked to perceived complexity. Experiment 2 tested whether the effect was modulated by distance. If angular shapes are associated with a threat, the effect may be stronger when they are presented within peripersonal space. This hypothesis was not supported. Experiment 3 tested whether preference for curves occurs when curved lines are compared to straight lines without angles. Sets of coloured lines (angular vs. curved vs. straight) were seen through a circular or square aperture. Curved lines were liked more than either angular or straight lines. Therefore, angles are not necessary to generate a preference for curved shapes. Finally, Experiment 4 used an implicit measure of preference, the manikin task, to measure approach/avoidance behaviour. Results did not confirm a pattern of avoidance for angularity but only a pattern of approach for curvature. Our experiments suggest that the threat association hypothesis cannot fully explain the curvature effect and that curved shapes are, per se, visually pleasant.  相似文献   

5.
Previous research has linked the concept of number and other ordinal series to space via a spatially oriented mental number line. In addition, it has been shown that in visual scene recognition and production, speakers of a language with a left‐to‐right orthography respond faster to and tend to draw images in which the agent of an action is located to the left of the patient. In this study, we aim to bridge these two lines of research by employing a novel method that measures the spatial bias produced by transitive sentences that use a wide variety of abstract and concrete verbs. Across four experiments, participants read sentences and then responded to probe words appearing on either the left or right sides of the screen. Probe words consisted of agents, patients, other words in the sentence, or newly encountered words. We found consistent lateral biases to responding to agents and patients, which appears to be independent of order of mention in the sentence but which does reflect a correspondence between position in the sentence and role in the causal sequence of the action. Our results also show that this spatial bias is driven by the use of the hands in two different ways: The left hand shows a greater sensitivity to the spatial effect than the right hand, and vocal responses produce no spatial effect.  相似文献   

6.
When placed in a water-filled maze, mice display a pronounced preference for the illuminated over the nonilluminated arm of the maze. Exposure to inescapable shock increased the time spent in the illuminated arm of the maze, and decreased the frequency of entries into the nonilluminated arm. When animals that had received shock entered the nonilluminated arm they exhibited more activity per second than nonstressed animals. Controllability over the stressor enhanced the preference for the illuminated arm; however, the contribution of this variable was dependent on the number of shock trials mice received. Following 180 escapable or inescapable shock presentations the preference for the illuminated arm was enhanced. The propensity to approach the illuminated arm declined following a greater number (360) of escapable shock trials, while the preference for the illuminated arm did not decline in mice that received inescapable shock. Both escapable and inescapable shock were also found to produce a transient disruption of discrimination performance in a task where animals were required to emit a contraprepared response (swim to dark), whereas these treatments were without effect on performance of the highly prepared response of approaching the illuminated arm. It is provisionally suggested that enhancement of the perseveration represents an innate response to stressful stimuli, but as animals learn mastery over the response contingencies, the persistence in adopting such a response strategy wanes. Moreover, despite the differential effects of escapable and inescapable shock on the perseverative tendency, discrimination accuracy may not be differentially affected by these treatments in a task where acquisition progresses quickly and where explicit cues are associated with the correct and incorrect arms of the maze.  相似文献   

7.
Visual psychophysics of simple graphical elements   总被引:2,自引:0,他引:2  
The accuracy with which graphical elements are judged was assessed in a psychophysical task that parallels the real-life use of graphs. The task is a variant of the Metfessel-Comrey constant-sum method, and an associated model based on Stevens's law is proposed. The stimuli were horizontal and vertical lines, bars, pie and disk slices, cylinders, boxes, and table entries (numbers). Stevens's law exponents were near unity for numbers and 1-dimensional elements but were also close to 1 for elements possessing 2 or 3 apparent dimensions--subjects accommodate extraneous dimensions that do not carry variation, changing the effective dimensionality of the stimulus. Judgment errors were small, with numbers yielding the best performance; elements such as bars and pie slices were judged almost as accurately; disk elements were judged least accurately, but the magnitude of the errors was not large.  相似文献   

8.
Where stimuli are possibly discriminable but do not elicit spontaneous differential looking it is customary to use one or other variation of the habituation–dishabituation method in order to investigate their discriminability, and the literature abounds with such studies. However, there are many variations on habituation–dishabituation procedures, varying both within and between the sensory modalities investigated. Additionally, infant attention is a dynamic process which is likely to change over time, and given the great variations in procedures it can often be difficult to know whether infants are giving a familiarity or a novelty preference at test, which can make interpretation of results a difficult, and often controversial problem. Houston‐Price and Nakai give some clear examples of the changing nature of infant preferences, and relate them particularly to the amount of familiarisation prior to testing. The model they favour (and which receives a good deal of support) is that put forward by (among others) Hunter and Ames (1988) in which preferences change over the course of familiarisation time, from preference for neither familiarity or novelty, to familiarity, to no preference, to a novelty preference. They suggest that ‘If an attentional shift from what is familiar to what is novel is always found as the encoding of a familiar stimulus… is completed… then the pattern of change in preference over time should provide crucial information regarding the identity of the obtained effect’. I will argue that this attentional shift is not always found, and that in many instances we need converging evidence in order to clarify experimental findings. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

9.
In many areas of science, research questions imply the analysis of a set of coupled data blocks, with, for instance, each block being an experimental unit by variable matrix, and the variables being the same in all matrices. To obtain an overall picture of the mechanisms that play a role in the different data matrices, the information in these matrices needs to be integrated. This may be achieved by applying a data‐analytic strategy in which a global model is fitted to all data matrices simultaneously, as in some forms of simultaneous component analysis (SCA). Since such a strategy implies that all data entries, regardless the matrix they belong to, contribute equally to the analysis, it may obfuscate the overall picture of the mechanisms underlying the data when the different data matrices are subject to different amounts of noise. One way out is to downweight entries from noisy data matrices in favour of entries from less noisy matrices. Information regarding the amount of noise that is present in each matrix, however, is, in most cases, not available. To deal with these problems, in this paper a novel maximum‐likelihood‐based simultaneous component analysis method, referred to as MxLSCA, is proposed. Being a stochastic extension of SCA, in MxLSCA the amount of noise in each data matrix is estimated and entries from noisy data matrices are downweighted. Both in an extensive simulation study and in an application to data stemming from cross‐cultural emotion psychology, it is shown that the novel MxLSCA strategy outperforms the SCA strategy with respect to disclosing the mechanisms underlying the coupled data.  相似文献   

10.
A row (or column) of an n×n matrix complies with Regular Minimality (RM) if it has a unique minimum entry which is also a unique minimum entry in its column (respectively, row). The number of violations of RM in a matrix is defined as the number of rows (equivalently, columns) that do not comply with RM. We derive a formula for the proportion of n×n matrices with a given number of violations of RM among all n×n matrices with no tied entries. The proportion of matrices with no more than a given number of violations can be treated as the p-value of a permutation test whose null hypothesis states that all permutations of the entries of a matrix without ties are equiprobable, and the alternative hypothesis states that RM violations occur with lower probability than predicted by the null hypothesis. A matrix with ties is treated as being represented by all matrices without ties that have the same set of strict inequalities among their entries.  相似文献   

11.
Aphasic and non-neurological patients grouped nouns on the basis of similarity of meaning. These word groupings served as input matrices for hierarchical clustering and multidimensional scaling analyses. The emergent structures suggest that, while the normal adult has a number of levels upon which to organize his lexicon, the adult aphasic's lexicon can be characterized as a set of partial entries that are tied to affective and situational data. The results also suggest that semantic feature representations derived from similarity-of-meaning judgments are of relevance in the study of factors which influence actual language performance.  相似文献   

12.
Precision and general computer mouse aiming performance by right-handers (RH-RM) and left-handers with right-handed mouse experience (LH-RM) and by left-handers with left-handed mouse experience (LH-LM) were compared. A number of performance measures, such as reaction time, time to reach a target, time to click on target, and cursor trajectory, were analyzed. Superficially, specific hand experience seemed to dictate performance asymmetries, but a closer look revealed interactions between hand preference and hand performance. That finding has implications for theories of handedness. In addition, precision and general directional aiming with the mouse cursor showed a clear right hand superiority in reaction time in both RH-RM and LH-RM subjects, whereas LH-LM subjects showed no lateral asymmetries. Finally, the overall time taken for the task, averaged across groups and conditions, favored the experienced hand by some 180 ms. In practical terms, that is not a large difference, especially because the difference will be reduced with practice. Thus, the use of the inexperienced hand can be advocated when there is a need to forestall or ameliorate repetitive stress in the experienced hand.  相似文献   

13.
Mainstream psychology in the 20th century has been conceived as a nomothetic science, but few psychological "laws" have been proposed. A PsycLit search of journal abstracts from 1900 to 1999 yielded a total of 3,093 "law" citations, or 22 per 10,000 entries, with two psychophysical laws (Weber's law and Stevens's power law) and two learning laws (Herrnstein's matching law and Thorndike's law of effect) as the most frequently cited. The number of law citations has been decreasing throughout the century, to 10 per 10,000 entries in the last decade, with few references to laws of recent origin. This could be the result of increasing doubts about the lawfulness of psychological processes coupled with a general preference for less ambitious terms (such as effects, principles, models, or functions).  相似文献   

14.
ABSTRACT

Starting in the preschool years, children show socially exclusive behaviors, such as intentionally leaving out another child from a ball game. Prior research investigating social exclusion understanding in preschoolers primarily used interview methods and it is clear that the verbal and cognitive skills necessary to identify and reason about social exclusion become more sophisticated with age. Yet it is unknown how children’s ability to identify social exclusion relates to their own behavior, such as their social preference for socially inclusive or exclusive individuals. Further, whether such social preferences remain stable or change across development is an open question. Thus, the current study investigated whether the ability to identify social exclusion develops in tandem with social preference behavior by assessing 3- to 6-year-old children’s (N = 256) identification of social exclusion and preferences between socially exclusive and inclusive agents. Five- to six-year-old children correctly identified social exclusion and preferred inclusive agents over exclusive agents across two experiments. Three- to four-year-old children could correctly identify social exclusion, but did not show evidence of a preference for inclusive agents over exclusive agents. Children were also able to detect implicit, nonverbalized social exclusion equally well as explicit, verbalized social exclusion across development. These findings suggest that young children’s social preferences are not wholly dictated by their ability to identify socially exclusive agents. This divergent pattern of social preference from identification has implications for interpreting social preference behavior in young children.  相似文献   

15.
Several definitions are in use for the derivative of an m × p matrix function F(X) with respect to its n × q matrix argument X. We argue that only one of these definitions is a viable one, and that to study smooth maps from the space of n × q matrices to the space of m × p matrices it is often more convenient to study the map from nq-space to mp-space. Also, several procedures exist for a calculus of functions of matrices. It is argued that the procedure based on differentials is superior to other methods of differentiation, and leads inter alia to a satisfactory chain rule for matrix functions.  相似文献   

16.
Relations between multidimensional scaling and three-mode factor analysis   总被引:3,自引:0,他引:3  
A combination is achieved of two lines of psychometric interest: a) multidimensional scaling and b) factor analysis. This is accomplished with the use of three-mode factor analysis of scalar product matrices, one for each subject. Two of the modes are the groups of objects scaled and the third mode is the sample of subjects. Results are an object space, a person space, and a system for changing weights given to dimensions and of angles between dimensions in the object space for individuals located at different places in the person space. The development is illustrated with data from an adjective similarity study.Supported in part by the Personnel and Training Branch of the Office of Naval Research under Contract Number 00014-67-A-0305-0003. A number of very helpful comments were made by an anonymous editorial reviewer forPsychometrika.During 1970–71 at the L. L. Thurstone Psychometric Laboratory, University of North Carolina.  相似文献   

17.
Adolescents participated in qualitative interviews (N?=?40) and permitted researchers to check their cell phone histories (N?=?35) for the content and frequency of text and call communications with parents. Communications focused predominantly on day-to-day “managerial” aspects of parent–child relationships but also facilitated emotional connections between adolescents and parents. Adolescents preferred to use texts to engage in managerial communications and calls to connect emotionally, but logistical constraints resulted in most cell phone communications between adolescents and parents involving calls. Participants communicated more with mothers than fathers, regardless of communication content or medium. This was true regardless of family structure, although gender-of-parent differences were accentuated for adolescents in mother-only households. This pattern was explained by both greater maternal accessibility and adolescent preferences for communication with mothers. Communications with fathers tended to occur either when mothers were not available or when the communication was focused on a highly specific set of stereotypically masculine content areas.  相似文献   

18.
潘玉芹  王东林  林文娟 《心理学报》2007,39(6):1041-1047
“抑郁症细胞因子假说”的提出为抑郁障碍的病因学研究提供了一个新的方向,为了探讨脂多糖(lipopolyaccharide,LPS)诱导的免疫激活与抑郁性行为产生之间的关系,本研究采用50只SD大鼠随机分为五组LPS400,LPS200,LPS50,LPS10,LPS0,分别于实验期第0天和第3天注入LPS400ug/kg,,200ug/kg,50ug/kg,10ug/kg和生理盐水。以糖精水偏爱,旷场行为和高架十字迷宫评定大鼠LPS注射后2小时,24小时,48小时的行为变化。结果显示一次LPS注射后2小时,LPS50,LPS200,LPS400组动物与生理盐水组动物相比较,其糖精水偏爱分数(p<0.01),旷场中的水平活动距离(p<0.01)和直立行为(p<0.01)以及高架十字迷宫中的闭合臂进入次数(p<0.01)和开放臂进入次数显著下降(p<0.01);重复注射后2小时LPS注射组动物的闭合臂进入次数显著降低(p<0.01);但LPS10组与生理盐水组动物在行为上没有差异,50ug/kg,200ug/kg和400ug/kg剂量的各组之间没有差异。LPS注射后24小时和48小时以及重复注射后大鼠的行为没有发现显著变化。提示LPS诱导的免疫激活对抑郁行为产生有一定的作用。免疫激活的细胞因子能够导致动物出现明显的抑郁性行为,但是这种行为缺乏长时程效应,因此LPS诱导的抑郁障碍的动物模型应用是非常有限的。免疫激活的前炎性细胞因子可能是导致抑郁障碍产生的其中一个原因而不是唯一原因。  相似文献   

19.
Rogers B  Brecher K 《Perception》2007,36(9):1275-1289
Helmholtz's famous pincushioned chessboard figure has been used to make the point that straight lines in the world are not always perceived as straight and, conversely, that curved lines in the world can sometimes be seen as straight. However, there is little agreement as to the cause of these perceptual errors. Some authors have attributed the errors to the shape of the retina, or the amount of cortex devoted to the processing of images falling on different parts of the retina, while others have taken the effects to indicate that visual space itself is curved. Helmholtz himself claimed that the 'uncurved lines on the visual globe' corresponded to 'direction circles' defined as those arcs described by the line of fixation when the eye moves according to Listing's law. Careful re-reading of Helmholtz together with some additional observations lead us to the conclusion that two other factors are also involved in the effect: (i) a lack of information about the distance of peripherally viewed objects and (ii) the preference of the visual system for seeing the pincushion squares as similar in size.  相似文献   

20.
Comprehensive data for children's time of day preference were collected with school children from 8 through 16 years of age (n = 989) using the Children's Morningness-Eveningness Preferences (CMEP) scale. Strong evidence was found that children's optimal time of day preference shifts toward evening at about 13 years of age. Additionally, gender and ethnic differences in time of day preference were also examined. There was no gender difference, but there was a tendency for ethnic differences among older children. An implication of these findings is that a mismatch between older children's time of day preferences and school start time may have a negative effect on their school performance and this effect could be greater for some ethnic groups than for others.  相似文献   

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