Nonmetric maximum likelihood multidimensional scaling from directional rankings of similarities

A maximum likelihood estimation procedure is developed for multidimensional scaling when (dis)similarity measures are taken by ranking procedures such as the method of conditional rank orders or the method of triadic combinations. The central feature of these procedures may be termed directionality of ranking processes. That is, rank orderings are performed in a prescribed order by successive first choices. Those data have conventionally been analyzed by Shepard-Kruskal type of nonmetric multidimensional scaling procedures. We propose, as a more appropriate alternative, a maximum likelihood method specifically designed for this type of data. A broader perspective on the present approach is given, which encompasses a wide variety of experimental methods for collecting dissimilarity data including pair comparison methods (such as the method of tetrads) and the pick-M method of similarities. An example is given to illustrate various advantages of nonmetric maximum likelihood multidimensional scaling as a statistical method. At the moment the approach is limited to the case of one-mode two-way proximity data, but could be extended in a relatively straightforward way to two-mode two-way, two-mode three-way or even three-mode three-way data, under the assumption of such models as INDSCAL or the two or three-way unfolding models.The first author's work was supported partly by the Natural Sciences and Engineering Research Council of Canada, grant number A6394. Portions of this research were done while the first author was at Bell Laboratories. MAXSCAL-4.1, a program to perform the computations described in this paper can be obtained by writing to: Computing Information Service, Attention: Ms. Carole Scheiderman, Bell Laboratories, 600 Mountain Ave., Murray Hill, N.J. 07974. Thanks are due to Yukio Inukai, who generously let us use his stimuli in our experiment, and to Jim Ramsay for his helpful comments on an earlier draft of this paper. Confidence regions in Figures 2 and 3 were drawn by the program written by Jim Ramsay. We are also indebted to anonymous reviewers for their suggestions.     

Auditorily elicited EEG desynchronization and synchronization: A review of Christina M. Krause's doctoral thesis

The present paper reviews the doctoral dissertation of Christina M. Krause, in which auditorily elicited EEG desynchronization (ERD) and synchronization (ERS) was studied in five experiments. These experiments which were conducted by Krause and co-workers are the first in which the ERD-method was systematically applied to the analysis of the perception and processing of complex auditory stimuli. The main conclusion is that listening to sounds elicits ERS, whereas cognitive and/or memory processes elicit ERD.     

Postural stabilization for the control of touching

We attempted to distinguish between task-related (supra-postural) and perceptual influences on postural motions. Two groups of participants had to make very light tactile contact with an adjacent pliable surface while standing with their eyes closed. In the absence of vision, such light touching with a finger is known to reduce sway. For one group, tactile contact with the surface was merely the result of extending the right forearm. For the other group, variability in the point of tactile contact had to be kept to a minimum. Touching reduced postural sway relative to non-touching only for participants in the latter group. The present results, in combination with others addressing similar task differences, question the assumption that information detected haptically and/or visually is used solely to reduce postural fluctuations. It seems that postural fluctuations are modulated to facilitate performance of tasks over and above the task of standing upright and still.     

在不同注意定向条件下是否出现返回抑制的知觉优先

返回控制中的知觉优先是指相对于非线索化位置,线索化位置的刺激被优先知觉到的现象。研究采用时序判断方法对不同注意定向下返回抑制的知觉优先现象进行了两个实验。实验１采用连续线索化的安排,发现当注意从线索化位置移开后知觉优先仍然存在;实验２采用同时呈现双线索的安排发现知觉优先也存在。     

时距知觉的心理学研究

本文回顾了近五十年来时距知觉的实验研究,对不同的理论模型、实验范式、实验方法以及主要时距判断规律作了较全面的评述,并进一步探讨了时距知觉研究未来的发展。     

直销人员心理品质研究与测评

本研究从直销的特点出发,运用自编“直销人员心理品质测评量表”对１８３名优秀直销商进行测试,并对测试结果进行因素分析,抽取出优秀直销商必备的五项主要心理品质,即自我控制力、成就动机、社会适应性、推销技巧、职业兴趣。     

SOCIAL INTERACTIONS IN THREE SUPPORTED EMPLOYMENT OPTIONS: A COMPARATIVE ANALYSIS

Controversy exists over the benefits that workers with severe disabilities accrue under different supported employment options. This study focused upon one benefit of supported employment: social integration. Direct observation procedures were used to assess the social interactions of 37 adults with severe disabilities in 18 employment programs representing three different supported employment contexts (individual, enclave, and work crew). Results indicated that workers employed in individual and enclave programs had significantly more contact with nondisabled persons than did members of work crews. No differences were detected in the social contact rate between disabled and nondisabled workers in individual versus enclave sites. Furthermore, few differences in type of interactions across the three different work options were revealed. Results suggest that both individual and enclave models are capable of facilitating social integration. However, characteristics of specific job sites, more so than the employment model per se, may determine whether a particular employment setting is conducive to social integration.     

Irrational action and irrational belief

Many philosophers agree with Socrates that it is not possible to perform an akratic action consciously and freely. They take this view because they assimilate the internal irrationality of such a performance to the internal irrationality of drawing a theoretical conclusion which contadicts one's premisses. This article develops some arguments against that assimilation. The extreme cost of theoretical self-contradiction is forming the belief both that something is so and that it is not so. This is impossible for anyone who understands what he is doing, and the impossibility can be explained: nothing could conceivably make such a conjunction of beliefs true. But the conjunction of a value-judgement judgment and an action that gets against it is different. Although it too is internally irrational, there is no property like truth which the value-judgement and his action ought both to possess, but cannot both possess. This article proposes a different model for akratic action, which might serve as a basis for disagreement with Socrates' view of it.     

College students' responding to and rating of contingency relations: The role of temporal contiguity

Two experiments investigated the role of temporal contiguity in college students' responding to and rating of contingency relations during operant conditioning. Schedules were devised that determined when but not whether appetitive or aversive events would occur. Subjects' reports concerning the schedules were obtained by means of a 200-point rating scale, anchored by the phrases “prevents the light from occurring” (−100) and “causes the light to occur” (+100). When tapping a telegraph key advanced the time of point gain, responding was maintained or increased and subjects gave positive ratings. When tapping a telegraph key advanced the time of point loss, subjects also gave positive ratings, but responding now decreased. When key tapping delayed the time of point gain, responding decreased and subjects gave negative ratings. When key tapping delayed the time of point loss, subjects also gave negative ratings, but responding now increased. These findings implicate response-outcome contiguity as an important contributor to causal perception and to reinforcement and punishment effects. Other accounts—such as those stressing the local probabilistic relation between response and outcome or the molar correlation between response rate and outcome rate—were seen to be less preferred interpretations of these and other results.