Danièle Dubois

Effects of Classification Context on Categorization in Natural Categories

The patterns of classification of borderline instances of eight common taxonomic categories were examined under three different instructional conditions to test two predictions: first, that lack of a specified context contributes to vagueness in categorization, and second, that altering the purpose of classification can lead to greater or lesser dependence on similarity in classification. The instructional conditions contrasted purely pragmatic with more technical/quasi-legal contexts as purposes for classification, and these were compared with a no-context control. The measures of category vagueness were between-subjects disagreement and within-subjects consistency, and the measures of similarity-based categorization were category breadth and the correlation of instance categorization probability with mean rated typicality, independently measured in a neutral context. Contrary to predictions, none of the measures of vagueness, reliability, category breadth, or correlation with typicality were generally affected by the instructional setting as a function of pragmatic versus technical purposes. Only one subcondition, in which a situational context was implied in addition to a purposive context, produced a significant change in categorization. Further experiments demonstrated that the effect of context was not increased when participants talked their way through the task, and that a technical context did not elicit more all-or-none categorization than did a pragmatic context. These findings place an important boundary condition on the effects of instructional context on conceptual categorization.

Influence of the Electric Guitar's Fingerboard Wood on Guitarists' Perception

The sound of a solid body electric guitar comes from the loudspeaker transducing into sound the string velocity. Because of mechanical string-structure coupling, the string vibration, and therefore the sound, substantially depends on the lutherie parameters. This study focuses on the comparison between ebony-fingerboard and rosewood-fingerboard guitars: is a change in the fingerboard wood perceived by the guitar players? In order to test the hypothesis that it is actually perceived, a psychological investigation is carried out. Two experimental methods are used: a free sorting task with recorded stimuli from the guitars (listening test) and a free verbalisation task where the guitarists play the guitars. In the listening test, the guitarists perceive differences between guitars, but the resulting clusters do not show an ebony/rosewood dichotomy. A linguistic analysis of the verbalisations exhibits psychological descriptors that are relevant for the discrimination of the wood of the fingerboard: PRECISION (referring to how each note stands out from others), and to a lesser extent ATTACK (referring to the guitars response to musicians gesture) and BALANCE (referring to the frequency content). This study is part of a broader project aiming at establishing an explicite relation between mechanics, perception, and lutherie. A physical interpretation of the psychologically-relevant descriptors is eventually proposed in order to use them as hypotheses in a further hypothetico-deductive approach starting from physics and using psychophysical methods.

The meaning of city noises: Investigating sound quality in Paris (France)

The sound quality of Paris (France) was investigated by using field inquiries in actual environments (open questionnaires) and using recordings under laboratory conditions (free‐sorting tasks). Cognitive categories of soundscapes were inferred by means of psycholinguistic analyses of verbal data and of mathematical analyses of similarity judgments. Results show that auditory judgments mainly rely on source identification. The appraisal of urban noise therefore depends on the qualitative evaluation of noise sources. The salience of human sounds in public spaces has been demonstrated, in relation to pleasantness judgments: soundscapes with human presence tend to be perceived as more pleasant than soundscapes consisting solely of mechanical sounds. Furthermore, human sounds are qualitatively processed as indicators of human outdoor activities, such as open markets, pedestrian areas, and sidewalk cafe districts that reflect city life. In contrast, mechanical noises (mainly traffic noise) are commonly describe...

A cognitive approach of urban soundscapes

The presented cognitive approach of noises in urban environments focuses on meaning and as such integrates linguistic, psychological, and acoustic conceptualizations and methodologies. It deals with the acoustic phenomena that are perceived, conceived, and said as relevant by the subjects. The productivity of this approach has been evaluated in two research programs. Experiments combining linguistic and psychological analyses showed that urban soundscapes include a complex combination of unpleasant and pleasant noises. The identity of the source and the temporal and spatial contexts of occurrence of the noises are present in subjects’ cognitive representation and influence their perception. Experiments on alarm signals showed that contextual contraints influence the perceptual thresholds of the signals, their identification, and their efficiency (contrasting signals as such with nonmeaningful noises). In conclusion, such a ‘‘situated’’ cognitive (and pluridisciplinary) approach allows (i) at a theoretical...

Identity and autonomy of psychology in cognitive sciences: some remarks from language processing and knowledge representation

Abstract The purpose of this paper is to sketch some remarks about the evolution of psychology within contemporary cognitive sciences and its consequences on the definition of the object of a (one) scientific psychology. Arguments are stated on empirical experience from interdisciplinary research and on experimental investigations in psycholinguistics and knowledge representation.

From classifications to cognitive categorization: the example of the road lexicon

Within a new paradigm of categorization which is currently being developed in cognitive research, one of the main phenomena which has to be taken into account, is typicality (representativeness, family resemblance…). The gradedness that it introduces into categorical structures entails reconsideration of the relationship between extension and intension within categorical structures as well as between them. This involves both technical aspects and theoretical considerations relating to the meaningfulness of mathematical models to explain cognitive structures. Our contribution bears on the use and the evaluation of different data analysis methods to get at the featural structure of non verbal concepts from their graded extensional representation. The case which is used is that of mental categories of roads and landscapes in order to illustrate the main concepts that mathematical models of cognitive structures must (and can) explain on formal, theoretical and practical levels.

A cognitive approach to soundscape research

The present research on cognitive categories for soundscapes focuses on their interpretations and can be seen as mediating between individual sensory experiences and collective representations shared in language and elaborated as knowledge. Results of field inquiries in Paris, Lyon, and Nantes are presented together with results from categorization of recorded soundscapes in laboratory conditions. Categories were identified by means of linguistic analyses of verbal comments and mathematical analyses of similarity judgments. Results indicate that people categorize environmental sounds on the basis of semantic features, namely source identity and pleasantness judgments, rather than perceptual features. Effects of noise on human subjectivity cannot be quantitatively measured thoroughly in terms of physical parameters: auditory judgments depend upon the meaning attributed to acoustic phenomena and noise sources, rather than on inherent properties of the acoustic signal. These findings highlight the fact that ...

Is pleasantness for soundscapes dimensional or categorical

This paper focuses on methodological issues regarding the dimensional or categorical properties of pleasantness for soundscapes. Sixteen sequences of urban soundscapes were recorded and reproduced with their real sound intensity, using techniques previously validated to produce the illusion of a real environment. The sequences were processed using two methods: free categorization and pair comparisons. The categorization method consisted of asking subjects to sort out the sequences according to pleasantness and to verbally qualify their categories. In the pair comparison task, subjects had first to choose, for each pair, which sequence was the most pleasant, and then to rate the pleasantness dissimilarity between the two sequences on a nine‐point scale. Categories and ratings were processed through a cluster analysis and interpreted in connection with a psycholinguistic analysis of the verbal comments. Binary choices were transformed onto a dimensional representation of pleasantness. The main results lead ...

Acoustic quality of musical instruments and categorization

The qualitative evaluation of high vintage musical instruments gives rise to several theoretical as well as technical questions. Depending on the experts, either instrument makers trained in various technologies or variously skilled and styled interpreters, the judgments rely on different criteria, regarding the object itself, its manipulations, as well as acoustic or aesthetic properties of the sounds it produces. Various experiments were run with classical guitars (Montchalin, 1993), harpsichords (Guyot, Castellengo, and Dumoulin, 1997), and violin bows (Saint‐Loubry and Besnainou, 1997). The judgments were processed in free categorization tasks of musical (listened or performed) sequences, followed by verbal comments on the partitions realized. The analysis of the psychological judgments of similarity and difference, and the linguistic processing of the verbal comments, led to the identification of the relevance of various perceptual modalities (not only acoustic but also kinaesthetic, haptic, and even...

Automatic Emergence of Categories from Linguistic Descriptions Using FXS

Abstract We are concerned with automatic processing of symbolic (linguistic) data and more specifically of featural descriptions of typical and less typical exemplars of semantic categories. The empirical data were linguistic descriptions of exemplars from 30 subjects, structured along linguistic (syntactic and semantic) categories, and processed with FXS software. The emergent categories allow to discuss (i) typicality vs. sub-categorization, (ii) distances between superordinate, prototypes, typical exemplars, and finally (iii) principles of categorization.