Observation of large-scale inhomogeneities in a granular metal

Abstract

Thick films of granular aluminium dispersed in a tellurium-rich matrix have been formed by co-deposition of the pure elements. Correlation of Rutherford backscattering and superconducting critical-field measurements demonstrates that the films are subdivided into compositionally and electrically distinct layers typically 400–600 Å thick extending across large areas of the specimens. Comparison with the superconducting properties of granular Al: Al₂O₃ supports earlier suggestions that similar layering is present in that system.     

What do I Think of Others in Relation to Myself? Moral Identity and Moral Inclusion in Explaining Prejudice

The aim of this article is to analyze the effect of moral identity on prejudice in conjunction with moral inclusion/exclusion attitudes. In particular, the hypothesis is that even if high moral identity people tend to be less prejudicial than low moral identity people, this result can be explained with reference to moral inclusion/exclusion attitudes. A questionnaire was distributed to 192 Italian subjects. According to the hypothesis, results show that moral identity is negatively correlated with blatant prejudice, but that this effect is completely mediated by the perception of moral inclusion/exclusion with the other groups. These results suggest that it is not how morally you behave (symbolization), or the relevance you give to moral traits for your identity (internalization), that have an effect on prejudice, but rather it is who you include within the moral community within which moral values apply. Copyright © 2012 John Wiley & Sons, Ltd.     

Synthesis of autonomous robots through evolution

Evolutionary robotics is the attempt to develop robots through a self-organized process based on artificial evolution. This approach stresses the importance of the study of systems that have a body and that are situated in a physical environment, and which autonomously develop their own skills in close interaction with the environment. In this review we briefly illustrate the method and the main concept of evolutionary robotics, and examine the most significant contribution in this area. We also discuss some of the contributions that this research area is making to the foundational debate in cognitive science.     

Detecting deception: adversarial problem solving in a low base-rate world

The work presented here investigates the process by which one group of individuals solves the problem of detecting deceptions created by other agents. A field experiment was conducted in which twenty-four auditors (partners in international public accounting firms) were asked to review four cases describing real companies that, unknown to the auditors, had perpetrated financial frauds. While many of the auditors failed to detect the manipulations in the cases, a small number of auditors were consistently successful. Since the detection of frauds occurs infrequently in the work of a given auditor, we explain success by the application of powerful heuristics gained from experience with deceptions in everyday life. These heuristics implement a variation of Dennett's intentional stance strategy, which is based on interpreting detected inconsistencies in the light of the Deceiver's (i.e., management's) goals and possible actions. We explain failure to detect deception by means of perturbations (bugs) in the domain knowledge of accounting needed to apply these heuristics to the specific context of financial statement fraud. We test our theory by showing that a computational model of fraud detection that employs the proposed heuristics successfully detects frauds in the cases given to the auditors. We then modify the model by introducing perturbations based on the errors made by each of the auditors in the four cases. The resulting models account for 84 of the 96 observations (i.e., 24 auditors × four cases) in our data.     

Hand gestures and perceived influence in small group interaction

A laboratory study was carried out to establish the relative importance of verbal and gestural behavior, as well as their interaction, for perceived social influence in more or less competitive small groups. Forty women (psychology students) participated in leaderless small group discussions of different sizes (four-member and eight-member): at the end, each member rated the perceived influence in decision-making of every other member. Verbal dominance coding is based on traditional quantitative conversational dominance (number of talk turns). Gestural coding (conversational, ideational, object-adaptor, self-adaptor gestures) is based on classical gesture classifications. Beside a substantial effect of verbal dominance, the main result is that frequency of object-adaptors and conversational (only in large groups) and ideational (in both small and large groups) gestures increases perceived influence scores particularly when the verbal dominance of the speaker is low.     

A Simon effect for depth in three-dimensional displays

We investigated whether the Simon effect occurs for the depth dimension in a 3-dimensional display. In Experiment 1, participants executed discriminative responses to 2 stimuli, a cross and a sphere, both 3-dimensional, which were perceived to be located near or far with respect to the participant's body. The response keys were located near and far along the participant's midline. Apparent stimulus spatial location (near or far) was irrelevant to the task. Results showed a depth Simon effect, attributable to the apparent stimulus spatial location. Experiment 2 replicated Experiment 1 with a different procedure. The 2 stimuli, a triangle and a rectangle, were 2-dimensional and were perceived as being located near or far from the participant's midline; the response keys were located near and far along the participant's midline. Results showed again the depth Simon effect. Experiment 3 was a control condition in which the 2 stimuli, drawings of a lamp and of a chair, had the same size, regardless of whether they appeared to be near or far. The depth Simon effect was replicated. A distribution analysis on data of Experiment 3 showed that the Simon effect increased as reaction times became longer. In Experiment 4, the position of the 2 stimuli, a circle and a cross, varied on the horizontal (right or left) dimension, whereas the position of the 2 responses varied along the depth (near or far) dimension. No Simon effect was found.     

Features of the selectivity for contrast polarity in contour integration revealed by a novel tilt illusion

We studied a novel illusion of tilt inside checkerboards due to the role of contrast polarity in contour integration. The preference for binding of oriented contours having same contrast polarity, over binding of opposite polarity ones (CP rule), has been used to explain several visual illusions. In three experiments we investigated how the binding effect is influenced by luminance contrast value, relatability of contour elements, and distance among them. Experiment 1 showed that the effect was indeed present only when the CP rule was satisfied, and found it to be stronger when the luminance contrast values of the elements are more similar. In experiment 2 the illusion was reported only with relatable edges, and its strength was modulated by the degree of relatability. The CP-rule effectiveness, thus, seems to depend on good continuation. The intensity of contrast polarity signals propagating from an oriented contour might be the less intense, the more its direction deviates from linearity. In experiment 3 we estimated the distance threshold and found it to be smaller than the one found for other illusions, arising with collinear fragments. This seems to show that the reach of the contrast polarity signal inside the association field of a contour unit is shorter along non-collinear orientations than along collinear ones.     

Mapping the perceptual structure of rectangles through goodness-of-fit ratings

Three experiments were carried out to investigate the internal structure of a rectangular frame to test Arnheim's (1974 Art and Visual Perception, 1988 The Power of the Center) proposals about its 'structural skeleton'. Observers made subjective ratings of how well a small probe circle fit within a rectangle at different interior positions. In experiment 1, ratings of 77 locations were highest in the center, decreased with distance from the center, greatly elevated along vertical and horizontal symmetry axes, and somewhat elevated along the local symmetry axes. A linear regression model with six symmetry-related factors accounted for 95% of the variance. In experiment 2 we measured perceived fit along local symmetry axes versus global diagonals near the corners to determine which factor was relevant. 2AFC probabilities were elevated only along the local symmetry axes and were higher when the probe was closer to the vertex. In experiment 3 we examined the effect of dividing a rectangular frame into two rectangular 'subframes' using an additional line. The results show that the primary determinant of good fit is the position of the target circle within the local subframes. In general, the results are consistent with Arnheim's proposals about the internal structure of a rectangular frame, but an alternative interpretation is offered in terms of the Gestalt concept of figural goodness.