Psychophysical Relations Research Articles

Integrating Compositional and Decompositional Analyses to Represent the Intervening Role of Perceptions in Evaluative Judgments

In the study of preference formation, compositional methods (e.g., linear compensatory attitude models) and decompositional techniques (e.g., conjoint analysis) have developed along relatively separate paths. The author attempts to integrate these two approaches via a two-stage model of evaluative judgment whose testing incorporates aspects of both analytic procedures. Specifically, the overall effect of objective product features on affect is broken down into a compositional relationship of affect to perceptions (i.e., attitude structure) and a decompositional analysis of the dependence of perceptions on product features (i.e., psychophysical relations). The approach is illustrated by a study of aesthetic preferences among piano performances differing in four factorially arrayed musical features (tempo, rhythm, dynamics, and phrasing). An integration of decompositional and compositional methods generates a summary path-analytic diagram that clearly represents the process wherein objective product features shape perceptions which, in turn, determine affect. This integrative approach appears to be applicable in several marketing contexts.

Psychophysical relations

Psychophysical relations

DISCRIMINABINITY OF FIXED‐RATIO SCHEDULES FOR PIGEONS: EFFECTS OF ABSOLUTE RATIO SIZE1

In a discrete-trial choice situation, 12 pigeons were trained to discriminate which of two different fixed ratios they had completed. Psychometric functions were obtained at three ratio requirements (i.e., with the larger ratio set at 10, 20, or 30 responses) by gradually reducing the size of the smaller value. Although different response biases developed across subjects, in each case accuracy decreased systematically with ratio difference regardless of absolute ratio requirements. Above-chance performances were maintained even at relative ratio differences of 10% or less. Estimates of the Weber fraction showed that, in general, discriminability improved with absolute ratio size up to 30 responses, and beyond, when the results of other studies are considered. A similar trend held for rats studied by other investigators in fixed-ratio "counting" tasks at lower requirements. In terms of a signal-detection analysis, performance was similar to that reported for other species and dimensions. Taken together, the results suggest that for this somewhat novel dimension the same psychophysical relations hold as are commonly observed for exteroceptive stimuli.

Visual backward masking and the area-detection relation

Contrary to expectations based on the well-documented positive relation between target area and detectability, half-black and half-white target disks were considerably more difficult to mask (easier to detect) with black rings than was a homogeneous black disk. The results, obtained by a forced-choice indicator response, can probably be attributed to the contour effects generated by the black-white disks. These findings indicate that the area-detection relation (and possibly other well-known psychophysical relations) may not generalize to masking situations.

Book Review: Psychophysical Relations in the Perception of Velocity

Book Review: Psychophysical Relations in the Perception of Velocity

PSYCHOPHYSICAL RELATIONS IN VISUAL PERCEPTION OF LENGTH, AREA AND VOLUME

Ekman, G., and Junge, K. Psychophysical relations in visual perception of length, area and volume. Scand. J. Psychol., 1961, 2, 1–10. — Subjective length, area and volume as functions of the corresponding stimulus variables were studied in three experiments. The exponents of the psychophysical power functions scattered around 1 for perception of ‘real’ space. For perspective drawings of cubes and spheres, however, the exponents were about 0.75. From a further analysis of the data it was tentatively concluded that perspective and shadow are insufficient cues to visual volume, and that the subjective scale reflects perception of area rather than volume, especially in the case of small stimuli.

Discrimination of hue as a function of wave length

SUMMARY AND CONCLUSIONS1. It has been shown previously by the present writer that the matrix of subjective similarities between spectral colors may be accounted for by five color factors, and that these color factors may be adequately represented by normal curves.2. Assuming that jnd's are proportional to subjective similarities in supraliminal comparisons, jnd's are inferred from our five normal color curves.3. The theoretical curve thus obtained is in good agreement with experimental data on wave length discrimination.The psychophysical relations under consideration may be described mathematically. The jnd is proportional to the subjective similarity, in small intervals,Δ λ = o (s)and the similarity scores are given by the matrix equationS = YY',where the elements of Y are ordinates of five normal curves.yi = fi (λ).Hence, in principleΔ λ = ψ (λ),i. e., the differential threshold is a function of wave length.The constants of this somewhat complex function are those of the five normal color curves. These...

Discriminal sensitivity on the subjective continuum

1. (1) It is pointed out that the relation between discriminal sensitivity and perceived intensity in the subjective dimension is an important problem which has attracted too little attention. There seems to be no single investigation directly centering on this question. 2. (2) A method is developed for investigating this relation. It is essentially a graphic procedure for differentiating R with respect to S in order to make possible a computation of discriminal dispersions or related measures in terms of R. 3. (3) The method is applied to a fictious numerical example. 4. (4) The same method is applied to published experimental data. It is found that the difference limen is an increasing linear function of intensity in the case of subjective weight, and an increasing, definitely non-linear function in the case of subjective salt intensity. 5. (5) There is indirect evidence that the difference limen in subjective units is constant in the case of brightness and pitch, but is an increasing function of intensity in the case of loudness. 6. (6) The case of qualitative or inter-dimensional variation is discussed. There is indirect evidence that subjective sensitivity is constant along the curvilinear continuum in the multidimensional subjective space of hue. 7. (7) An hypothesis advanced by Stevens and collaborators is contradicted by brightness data but supported by color data. 8. (8) Relations between sensitivity and position in the subjective continuum may possible be ascribed to central processes, which makes them more promising objects of investigation than conventional psychophysical relations which also depend on highly specific peripheral factors.

Discriminal Sensitivity on the Subjective Continuum

SUMMARY(1) It is pointed out that the relation between discriminal sensitivity and perceived intensity in the subjective dimension is an important problem which has attracted too little attention. There seems to be no single investigation directly centering on this question.(2) A method is developed for investigating this relation. It is essentially a graphic procedure for differentiating R with respect to S in order to make possible a computation of discriminal dispersions or related measures in terms of R.(3) The method is applied to a fictitious numerical example.(4) The same method is applied to published experimental data. It is found that the difference limen is an increasing linear function of intensity in the case of subjective weight, and an increasing, definitely non-linear function in the case of subjective salt intensity.(5) There is indirect evidence that the difference limen in subjective units is constant in the case of brightness and pitch, but is an increasing function of intensity in the case of loudness.(6) The case of qualitative or inter-dimensional variation is discussed. There is indirect evidence that subjective sensitivity is constant along the curvilinear continuum in the multidimensional subjective space of hue.(7) An hypothesis advanced by Stevens and collaborators is contradicted by brightness data but supported by color data.(8) Relations between sensitivity and position in the subjective continuum may possible be ascribed to central processes, which makes them more promising objects of investigation than conventional psychophysical relations which also depend on highly specific peripheral factors.

Review of On Psycho-physical Relations of the Association Experiment.

Review of On Psycho-physical Relations of the Association Experiment.

On psychophysical relations of the associative experiment.

On psychophysical relations of the associative experiment.

For a Medical Jury.

Brackettville, Texas, April 15, 1894. To the Editor: —I hasten to the support of the suggestion of your New York contributor (in No. 13 current volume) for revision of the statutes in manner to provide for a jury of medical men in all cases where medical evidence is required. I would establish at least one such jury in every county. I would arraign for trial all professors of clinical morphology, wherever they may be found at large, and all speculators on the psycho-physical relations of man, whether in the East or West. I would not try them by rule of law, but simply attempt to find out what is the matter with them. If it is the physician's business intelligently to treat disease, then here is fine field for future development. The jury would be required to clear and determine such questions as this: What is the

THE PSYCHO-PHYSICAL RELATIONS OF MAN, CONSIDERED FROM THE STANDPOINT OF A PRACTITIONER OF MEDICINE.Read before the Binghamton Academy of Medicine Oct. 19, 1893.

(Continued from page 450). Excessive fright has often been productive of grave results, and in many instances, of sudden death. Among the grave diseases induced by fright are mentioned typhus, epilepsy and apoplexy. Fear excites especially enuresis, diarrhea and generally produces a relaxation of the sphincters of the mucous passages, causes abortion and predisposes to attacks of contagious and miasmatic disease, while it aggravates every disorder and often renders them fatal. We might, if time would permit, refer to many recorded cases of positive and even fatal illness being induced by the imagination only, but one instance or illustration must suffice. Lord Stanhope relates the following: "An English physician while walking with a friend and conversing with him upon the power of the imagination in its effect upon the health observed a robust and healthy laborer approaching; to prove to his friend the truth of his opinion he accosted the

THE PSYCHO-PHYSICAL RELATIONS OF MAN, CONSIDERED FROM THE STANDPOINT OF A PRACTITIONER OF MEDICINE.Read before the Binghamton Academy of Medicine Oct. 19,1893.

THE PSYCHO-PHYSICAL RELATIONS OF MAN, CONSIDERED FROM THE STANDPOINT OF A PRACTITIONER OF MEDICINE.Read before the Binghamton Academy of Medicine Oct. 19,1893.