MULTIDIMENSIONAL SCALING OF GEOMETRICAL FIGURES

In two experiments with geometrical figures as stimuli, constructed in order to generate perceptual variation of roundness and height, four multidimensional scaling methods were compared, two metric and two nonmetric. The methods gave similar solutions. The fact that the solutions could be interpreted in accordance with expectations, points to the validity of the methods.     

Similarity relations among synesthetic stimuli and their attributes

Four experiments examined the similarity relations that exist among bimodal attributes that correspond synesthetically (e.g., white color and high pitch) and among stimuli formed by combining these attributes either congruently (e.g., white/high, black/low) or incongruently (e.g., white/low, black/high). Previous research suggests two hypotheses: (a) Synesthetic stimuli are compared as wholes on the basis of their overall similarity, and (b) nonidentical congruent stimuli are more dissimilar than nonidentical incongruent stimuli. In these four experiments, similarity among either individual attributes (Experiments 1 and 4) or bimodal stimuli (Experiments 2 and 3) was measured by either ratings or response latencies; similarity judgments were scaled with an individual differences scaling procedure (SINDSCAL). Stimulus comparisons were fit well by a Euclidean but not a city-block metric, supporting the overall similarity hypothesis. However, there was little evidence that subjects perceived congruity/incongruity among stimulus wholes, even though subjects were sensitive to correspondence/noncorrespondence among attributes. These results were replicated in four additional experiments using larger stimulus sets. A two-process account is proposed in which stimulus formation (intersensory processing) occurs independently of the abstraction of cross-sensory meaning (figurative processing).     

A COMPARATIVE STUDY OF SOME MULTIDIMENSIONAL VECTOR MODELS FOR SUBJECTIVE SIMILARITY

E kehammar B. A comparative study of some multidimensional vector models for subjective similarity. Scand. J. Psychol ., 1972, 1 3 , 190–197.—h this report, two theoretical vector models for subjective similarity were deduced from a "content" definition of subjective similarity. One of the derived similarity equations proved in empirical model testing to describe the similarity principle in perception of form better than earlier, similar models. Deviations between observed similarity estimates and values expected according to the model are discussed, among other things, in terms of the heterogeneity of the stimulus set.     

The role of discontinuities in the perception of subjective figures

Recently we proposed a theory of visual interpolation (Kellman & Shipley, in press) that addresses a variety of unit formation phenomena, including the perception of partly occluded objects and subjective figures. A basic notion of the theory is that discontinuities in the first derivative of projected edges are the initiating conditions for interpolation of boundaries that are not physically specified. In this paper, we report four experiments in which this claim was tested in the domain of subjective figures. Experiments 1 and 2 demonstrate that discontinuities in the first derivative of the edges of inducing elements have a clear effect on the frequency of report and the perceived clarity of simple subjective figures. Similar effects are found when unfamiliar subjective figures and inducing elements are used (Experiment 3). Experiment 4 rules out the possibility that the discontinuities in the first derivative merely add to the clarity of subjective figures. These experiments suggest that first-order discontinuities play a central role in unit formation.     

Representations of qualitative and quantitative dimensions

Geometric representations of psychological dimensions are analyzed and compared to an alternative set-theoretical approach. Judgments of similarity between forms and figures reveal the following effects: (a) qualitative attributes are curved relative to quantitative attributes, contrary to intradimensional subtractivity; (b) quantitative attributes augment differences in qualitative attributes, contrary to interdimensional additivity; (c) adding a new dimension with a fixed value increases similarity, contrary to translation invariance. The implications of these results to multidimensional representations of proximity data are discussed.     

The poggendorff illusion with subjective contours

Gregory (1972) has claimed that the Poggendorff misalignment effect occurs when the collinear obliques are separated by subjective rather than real contours. He used two figures to demonstrate this variant of the illusion. Two experiments to test the claim are reported. The first showed that apparent misalignment in one of the two original figures is no greater than that with two obliques alone (the oblique line effect), but misalignment in the other is greater than with two oblique lines and than with a control without subjective contours. The second experiment showed that apparent misalignment in the second figure was less than in two control figures without subjective contours. Since this reduced effect was probably due to the nature of the intersection between the oblique and a semi-circular element, the role of subjective contours remains unsettled.     

Availability,Similarity, and Gender as Determinants of Adolescent Peer Acceptance1

Attributes of accepted classmates were investigated as a function of (a) respondent-target similarity, (b) availability of desirable peers, (c) gender of respondent and accepted peers, and (d) level of intimacy of the social contact. It was assumed that availability would play a greater role than was previously recognized, in determining attributes of accepted peers in casual as well as intimate contacts, and same-gender and opposite-gender acceptance of males and females would be affected differentially by availability and similarity. Seven hundred and fitly-five 6th, 7th. and 8th grade male and female students indicated their readiness to engage in closer or more casual contacts with each of their classmates, using the Interpersonal Relationship Assessment Technique. It was found that in more superficial relations attributes of accepted peers tended to reflect availability of desirable peers (mean level of desirable student attributes in class), but not respondent-peer similarity; whereas readiness to maintain more intimate contacts with peers was significantly associated with similarity between respondent and accepted peers, as well as availability of desirable peers. It was found further that availability and similarity play different roles in determining acceptance of same-gender or opposite-gender peers by boys and by girls. These results were replicated over four levels of intimacy and four different student attributes.     

A MULTIDIMENSIONAL SCALING APPROACH TO THE PERCEPTION OF ART. I

G oude G. A multidimensional scaling approach to the perception of art. I. Scand. J. Psyckol ., 1972, 1 3 , 258–271.—-Five experiments with similarity estimation and ratio estimation of experiences of art (paintings) were used for testing a similarity model for multidimensional scaling. A multidimensional analysis gave five interpreted factors. Graphical estimations were compared with numerical estimations. Results from naive observers were related to results from a specialist group.     

Effects of similarity on apparent motion and perceptual grouping

Effects of similarity in colour, luminance, size, and shape on apparent motion and perceptual grouping were examined in part 1 in two parallel experiments on the same seven subjects. In both experiments, the effect of similarity was compared with that of proximity in competitive, bistable stimulus situations. A combination of a larger horizontal separation between the homogeneous stimulus elements and a smaller constant vertical separation between heterogeneous stimulus elements produced two kinds of apparent motion (or perceptual grouping) with equal probabilities. Such matched separations between homogeneous stimulus elements were obtained by the double staircase method in various stimulus conditions. In both experiments on apparent motion and perceptual grouping matched separation was found to increase as the difference between the heterogeneous stimulus elements increased. High correlations (0.71 to 0.94) of matched separations were found between apparent motion and perceptual grouping in four stimulus series: colour, luminance, size, and shape. Six of the seven subjects were also tested in part 2. Here, the effects of differences were found to work additively across different perceptual attributes in both phenomena, when multiple differences were combined in heterogeneous elements. The experimental results are discussed from the point of view that apparent motion is an example of perceptual constancy.     

Visual evoked potentials elicited by subjective contour figures

In order to investigate the relationship between the appearance of illusory figures and the wave form of visual evoked potentials (VEPs), 8 different visual pattern stimuli were presented to 8 normal subjects. Four of the stimuli (experimental stimuli) produced subjective figures and contours (squares and discs). The 4 other stimuli (reference stimuli), although equal to the experimental stimuli in the amount of physical energy, did not produce the illusion of squares or discs. Electrodes were placed on the scalp at central and occipital locations. Three prominent peaks in the occipital record were observed in all subjects. An amplitude difference of VEP N180 (N2) between the subjective figures and the reference stimuli was found in the values for each subject. Enhancement of the VEP of the illusory figure stimuli was observed for a specific component (N2), whereas the amplitude values at the central components and the occipital P120 (P2) and P280 (P3) were almost the same as the reference values. The VEP (N2 component) amplitude enhancement at the occipital area for subjective figure stimuli suggests that illusory contour formation takes place at higher levels in the visual system. This was known from experiments using dichoptic presentation.     

Kinetic subjective contours

Continuous changes in spatially separated figures can evoke perception of subjective contours and figures in physically homogeneous space between them. This occurs when all of the interruptions in the objectively present patterns (inducing elements) can be seen as caused by a unitary figure partly occluding them. Two experiments demonstrated and explored this phenomenon. In both, displays were presented to subjects under three conditions. In one condition, stationary inducing elements were shown as they would be interrupted by a figure rotating in front of them. In another condition, the background and inducing elements rotated, with interruptions occurring as if a stationary figure were in front. In a third condition, observers were shown 10 static views taken from the figure-rotation sequence for each display. Subjects consistently perceived unitary central figures with well-defined forms and clear edges from pattern changes given by figure movement and background movement. As with static subjective figures, kinetic subjective figures appear in front of, partly occluding, the inducing elements. These percepts form rapidly, and they depend upon temporal relations rather than upon information present in momentary views. Subjects occasionally reported subjective edges or a central figure in the stationary displays in Experiment 1, but not at all in Experiment 2, in which guessing tendencies were reduced by more specific instructions. The existence of kinetic subjective contours suggests that the visual system readily utilizes relationships among occlusion events separated in space and time. The minimum conditions for contour perception require neither information all along an edge nor simultaneous specification of the edge at two or more places.     

Are the effects of attention on speed judgments genuinely perceptual?

A number of studies in recent years have suggested that exogenous and endogenous attention might enhance the perceived magnitude of various perceptual attributes, such as contrast and motion speed. Those studies have generally used comparative judgments as a measure to assess the point of subjective equality; however, similarity judgments have been proposed as possibly less prone to decision biases (Schneider & Komlos, 2008). In three experiments, using a similarity judgment task, we did not find any evidence of motion speed enhancement by exogenous attention. We suggest that the effect revealed by comparative judgments arises at the decisional, rather than the perceptual, stage.     

The Roles of Similarity in Transfer: Separating Retrievability From Inferential Soundness

Similarity is universally acknowledged to be central in transfer, but recent research suggests that its role is complex. The present research attempts to isolate and compare the determinants of similarity-based access to memory and the determinants of the subjective soundness and similarity of a match. We predicted, based on structure-mapping theory, that subjective soundness would depend on the degree of shared relational structure, particularly higher-order structure such as causal bindings. In contrast, we predicted that memory retrieval would be highly sensitive to surface similarities such as common object attributes. To assess retrievability, in three studies, subjects were asked to read a large set of stories and were later given a set of probe stories that resembled the original stories in systematically different ways; e.g., purely relational analogies, surface-similarity matches, or overall (literal similarity) matches. Subjects were told to write out any of the original stories that came to mind. To assess subjective soundness, independent subjects (and also the same reminding subjects) were asked to rate the inferential soundness of each pair; i.e., how well inferences true of one story would apply to the other. As predicted, subjective soundness was highly related to the degree of common relational structure, while retrievability was chiefly related to the degree of surface similarity. Ratings of the similarity of the pairs did not predict the retrievability ordering, arguing against the possibility that the retrieval ordering simply reflected overall similarity. Further, a fourth study demonstrated that subjects given a forced-choice recognition task could discriminate between possible matches on the basis of relational structure, ruling out the possibility that the poor relational retrieval resulted from forgetting or failing to encode the relational structure. We conclude that there is a dissociation between the similarity that governs access to long-term memory and that which is used in evaluating and reasoning from a present match. We describe a model, called MAC/FAC ("any are called but few are chosen"), that uses a two-stage similarity retrieval process to model these findings. Finally, we speculate on the implications of this view for learning and transfer.     

内隐联想测验中他人重要性对自我心理表征的影响

联合采用联想匹配任务和内隐联想测验（IAT）任务，考察了自我—他人分类中的他人重要性对自我—高奖赏相似性的影响。研究将中性的几何图形与自我、不同重要性的他人（实验一为陌生人，实验二为朋友）建立联结，并将自我（暂时建立联结的图形）高奖赏联合任务与自我低奖赏联合任务下的反应差异（即IAT值）作为自我—高奖赏相似性的指标，结果表明：（1）联想匹配任务中自我和朋友以及自我和陌生人之间都存在显著的自我优势效应；（2）IAT任务中，自我和高奖赏只在他人为朋友的自我—他人分类判断时才具有相似性，而他人为陌生人时二者不具有相似性。这说明他人重要性改变了自我的心理表征。     

Prototype formation from imaged, kinesthetically, and visually presented geometric figures

The issue of prototype formation from simple geometric figures presented in various modes was studied in four conditions. Base figures and their exemplars were scaled in terms of their physical similarity, which was considered to reflect cognitive similarity. Geometric exemplars were visually presented, imaged by the subject, and kinesthetically presented. Following initial presentation, a recognition task was given in which some old items, some new items, and the prototype (also a new item) were presented in the same modality as originally perceived. The results indicate that prototype formation spans a wide class of human experiences and that internal representations of geometric figures derived from experiences with one modality tend to be second-order isomorphic with similar experiences derived from another modality.     

内隐联想测验中他人重要性对自我心理表征的影响

联合采用联想匹配任务和内隐联想测验（IAT）任务,考察了自我—他人分类中的他人重要性对自我—高奖赏相似性的影响。研究将中性的几何图形与自我、不同重要性的他人（实验一为陌生人,实验二为朋友）建立联结,并将自我（暂时建立联结的图形）高奖赏联合任务与自我低奖赏联合任务下的反应差异（即IAT值）作为自我—高奖赏相似性的指标,结果表明：（1）联想匹配任务中自我和朋友以及自我和陌生人之间都存在显著的自我优势效应;（2）IAT任务中,自我和高奖赏只在他人为朋友的自我—他人分类判断时才具有相似性,而他人为陌生人时二者不具有相似性。这说明他人重要性改变了自我的心理表征。     

A generalized distance function for preferential choices

Many cognitive theories of judgement and decision making assume that choice options are evaluated relative to other available options. The extent to which the preference for one option is influenced by other available options will often depend on how similar the options are to each other, where similarity is assumed to be a decreasing function of the distance between options. We examine how the distance between preferential options that are described on multiple attributes can be determined. Previous distance functions do not take into account that attributes differ in their subjective importance, are limited to two attributes, or neglect the preferential relationship between the options. To measure the distance between preferential options it is necessary to take the subjective preferences of the decision maker into account. Accordingly, the multi‐attribute space that defines the relationship between options can be stretched or shrunk relative to the attention or importance that a person gives to different attributes describing the options. Here, we propose a generalized distance function for preferential choices that takes subjective attribute importance into account and allows for individual differences according to such subjective preferences. Using a hands‐on example, we illustrate the application of the function and compare it to previous distance measures. We conclude with a discussion of the suitability and limitations of the proposed distance function.     

Connecting the horizontal dimension of social comparison with self-worth and self-confidence

Multilevel modeling of undergraduates (N = 229) event-contingent records of naturalistic social comparison experiences revealed distinct correlates of the horizontal (similar-different) dimension and vertical (better-worse) dimension of comparisons. Complementing past studies showing associations between the horizontal dimension and communal dispositions and experiences, the current study showed that the horizontal dimension also is associated with agentic dispositions and experiences such as self-worth and self-confidence. For example, participants perceived more similarity when comparing with targets' desirable attributes than with targets' undesirable attributes and perceiving similarities with desirable target attributes (and dissimilarities with undesirable target attributes) enhanced their self-confidence. Participants higher in self-worth (high in self-esteem and low in depression) were more discriminating in their experiences of similarity and connection; specifically, they reported more similarity and connection when targets' attributes were desirable but less connection the more targets' attributes were inferior to their own.     

Object identification: The mental representation of physical and conceptual attributes

In two experiments, subjects indicated whether two pictures of familiar objects were equivalent. The picture pairs were identical, showed the same object in various perspectives and states, or showed different objects with varying degrees of conceptual relatedness. In Experiment 1, the equivalence criterion for judging the picture pairs was varied between subjects (identity of pictures; conceptual equivalence of objects at subordinate, basic, or superordinate level). The reaction times of the four subject groups suggest that a pictorial stimulus is not always mentally represented in the same way, and that the instructions given determine which attributes of the stimulus are represented. In Experiment 2, the visual similarity of the picture pairs was varied. The results indicate, at least with a basic-level equivalence instruction, that not only perceptual, but also non-perceptual, functional attributes are represented—namely, those that, according to Rosch et al. (1976), are common to the members of a superordinate category.     

Spatial metrics of integral and separable dimensions

Two experiments were conducted to investigate the relationship between dimensional integrality and the form of the combination rule or spatial metric used in a similarity judgment task. In Experiment 1, two groups of eight subjects judged the dissimilarity of all pairwise combinations of 12 rectangles differing in height and width (integral dimensions) or 12 circles differing in size and diameter orientation (separable dimensions). The dimensional organization and spatial metric of both sets of dimensions were determined. The results showed that differences in height and width contributed independently to judgments of the overall dissimilarity of rectangles and that these dimensions were combined using a Euclidean metric. In contrast, substantial interactions between circle size and diameter orientation were found. Combinations of these dimensions also appeared to violate the triangle inequality implying that no spatial metric was appropriate. In Experiment 2, parallelogram size and tilt were similarly analyzed. Although some degree of dimensional interaction was observed, it was found that on the average these dimensions were combined using a city-block metric. In a subsequent speeded classification task, orthogonal interference was observed, which suggested that size and tilt are integral dimensions. The implications of both experiments for the supposed association between the Euclidean metric and dimensional integrality are discussed.