Theory Of Subjective Preference Research Articles

Optimal Volume for Concert Halls Based on Ando’s Subjective Preference and Barron Revised Theories

The Ando-Beranek’s model, a linear version of Ando’s subjective preference theory, obtained by the authors in a recent work, was combined with Barron revised theory. An optimal volume region for each reverberation time was obtained for classical music in symphony orchestra concert halls. The obtained relation was tested with good agreement with the top rated halls reported by Beranek and other halls with reported anomalies.

Acoustical measurements of sound fields between the stage and the orchestra pit inside an historical opera house

To clarify the relationship of the sound fields between the stage and the orchestra pit, we conducted acoustical measurements in a typical historical opera house, the Teatro Comunale of Ferrara, Italy. Orthogonal factors based on the theory of subjective preference and other related factors were analyzed. First, the sound fields for a singer on the stage in relation to the musicians in the pit were analyzed. And then, the sound fields for performers in the pit in relation to the singers on the stage were considered. Because physical factors vary depending on the location of the sound source, performers can move on the stage or in the pit to find the preferred sound field.

Theory of acoustic design of opera house and a design proposal

First of all, the theory of subjective preference for sound fields based on the model of auditory-brain system is briefly mentioned. It consists of the temporal factors and spatial factors associated with the left and right cerebral hemispheres, respectively. The temporal criteria are the initial time delay gap between the direct sound and the first Reflection (Dt1) and the subsequent reverberation time (Tsub). These preferred conditions are related to the minimum value of effective duration of the running autocorrelation function of source signals (te)min. The spatial criteria are binaural listening level (LL) and the IACC, which may be extracted from the interaural crosscorrelation function. In the opera house, there are two different kind of sound sources, i.e., the vocal source of relatively short values of (te)min in the stage and the orchestra music of long values of (te)min in the pit. For these sources, a proposal is made here.

Evaluation of sound fields in a concert hall involving scattered reflections applying the subjective preference theory

Convex tilted rear walls in a stage enclosure, an array of circular columns installed in front of walls, and triangular reflectors above the stage were newly adopted as scattering obstacles in an acoustic design of Tsuyama Music Cultural Hall, called “Bell Folêt Tsuyama.” The fundamental shape of the hall was designed using the theory of subjective preference. To calculate the effects of scattered reflections on a sound field in a real concert hall is extremely laborious. For this reason, the evaluation of effects of scattered reflections on the sound field in the hall was made experimentally by use of a 110 acoustical scale. After construction of the hall, therefore, sound fields of the hall, which involves scattered reflections caused by the tilted convex rear, by the array of circular columns, and by the triangular reflectors, were measured using four orthogonal physical factors (LL, Δt1, Tsub, IACC) described in the theory and the acoustical character of these scattering obstacles was clarified. Results clearly showed that these new attempts on scattered reflections substantially improved the quality of the sound field in the hall. Thesis advisor: Yoichi Ando Copies of this thesis written in English can be obtained from Yukio Suzumura. E-mail address: ysuzu11@lapis.plala.or.jp

In search of 'the good life' for demented elderly.

It may seem paradoxical to speak of the 'good life' for demented elderly. Many people consider dementia to be a life-wrecking disease and nursing homes to be terrible places. Still, it is relevant to ask how we can make life as good as possible for demented nursing home residents. This paper explores what three standard philosophical accounts of well-being--subjective preference theory, objectivist theories, and hedonism--have to say about the good life for demented people. It is concluded that the relevant differences between the various philosophical theories manifest themselves not so much in their general account of the substantial content of 'the good life' but in a number of specific controversies. These concern the nature of well-being, the necessity of endorsement by the patient, the value of experience and the need for experiences to be rooted in reality. Moreover, it is argued that further research should pay detailed attention to the process of dementia and to the effects of this process on patients' identities, self-conceptions, capacities, preferences, values and the like, and that a narrative approach which incorporates the factor time may offer a more comprehensive account of the good life for demented elderly.

SUBJECTIVE PREFERENCE FOR SOUND SOURCES LOCATED ON THE STAGE AND IN THE ORCHESTRA PIT OF AN OPERA HOUSE

The present study investigates whether the subjective preference theory can be applied to the sound field in an opera house. Paired-comparison tests were conducted to obtain scale values of subjective preference. As the source locations of the music on the stage and in the orchestra pit were moved, listeners were asked to give their acoustical preference. The acoustical factors at each listening position were obtained from the interaural cross-correlation function and binaural impulse responses measured at each listening position. The relationship between the scale values of subjective preference and orthogonal acoustical factors ( LL, IACC, τ IACC , Δt 1 for the pit source, Δt 1 for the stage, T sub for the pit source, and T sub for the stage source) was determined by using factor analysis, which shows that the preference theory is applicable. Total scores obtained from factor analysis and measured scale values are in good agreement.

CORRELATION FACTORS DESCRIBING PRIMARY AND SPATIAL SENSATIONS OF SOUND FIELDS

The theory of subjective preference of the sound field in a concert hall is established based on the model of human auditory–brain system. The model consists of the autocorrelation function (ACF) mechanism and the interaural crosscorrelation function (IACF) mechanism for signals arriving at two ear entrances, and the specialization of human cerebral hemispheres. This theory can be developed to describe primary sensations such as pitch or missing fundamental, loudness, timbre and, in addition, duration sensation which is introduced here as a fourth. These four primary sensations may be formulated by the temporal factors extracted from the ACF associated with the left hemisphere and, spatial sensations such as localization in the horizontal plane, apparent source width and subjective diffuseness are described by the spatial factors extracted from the IACF associated with the right hemisphere. Any important subjective responses of sound fields may be described by both temporal and spatial factors.

Acoustic measurements and the individual subjective evaluation for sound fields

Acoustical measurements and individual subjective evaluations for sound fields were performed based on a model of the human auditory-brain system and subjective preference theory. In the acoustic measurement section, orthogonal factors in historical opera houses and outdoor sound fields in forests are discussed. In the subjective evaluation section, individual differences and intra-individual changes of subjective preference are described in terms of the orthogonal factors. The main conclusions are as follows: (1) In acoustic measurements in a forest and in a bamboo forest, it is found that multiple scattering effects between trees or bamboo improve IACC; (2) Results of a preference test in an existing opera house show that subjective preference theory can be applied to opera houses, including the orchestra pit and the box seats; (3) Coefficient is introduced for individual preference in a sound field; and (4) The investigations of preference tests in relation to listening level (LL) and subsequent reverberation time (Tsub) for a simulated sound field show that subjects with a large value of α have small intra-individual changes, so the range of its preferred value is small. On the other hand, subjects with small value have minor preference as its parameter is changed. Thesis advisor: Yoichi Ando Copies of this thesis written in English can be obtained from Hiroyuki Sakai, Graduate School of Science and Technology, Kobe University, Rokkodai, Nada, Kobe 657-8501 Japan. E-mail address: sakaih@kobe-u.ac.jp.

Reverberance and its control in relation to the physical factors of sound fields in halls

Based on the theory of subjective preference, the author investigated the effects of the set of four orthogonal physical factors (listening level, initial time delay gap between the direct sound and the first reflection, subsequent reverberation time, and IACC) on the reverberance of sound fields. The study clarifies how much both temporal and spatial factors contribute to reverberance. Experiments were conducted to determine the effects of the physical factors on reverberance in simulated sound fields and in actual halls. Scale values of reverberance for both music and speech signals were obtained by the paired-comparison method. The results of these experiments show that these four factors affect the scale values of reverberance independently, and that the scale values of a sound field at any seat in a room can be calculated by the linear combinations of these factors. On the basis of the results from this and previous studies, some methods for controlling the reverberance of sound fields in an actual hall are proposed. The results of this study will allow the design of various reverberances for sound fields that are optimal for various source signals with its effective duration of autocorrelation function, (e)min. Thesis advisor: Yoichi Ando Copies of this thesis written in English can be obtained from Shigeo Hase, Theater Design Laboratory Co., 2-13-26 Makinohonmachi, Hirakata, Osaka, 573-1144 Japan. E-mail address: shigeo.hase@nifty.ne.jp

Computational systems for sound fields, as tools in design and diagnosis

Computational systems for design and diagnosis of sound field were developed. The concept of these systems are based on the model of human auditory-brain system [Y. Ando, Architectural Acoustics -Blending Sound Sources, Sound Fields, and Listeners (AIP/Springer-Verlag, New York, 1998)], including the autocorrelation mechanisms, interaural cross-correlation mechanism, and the specialization of the human cerebral hemispheres. Thesis consists of following four parts: (1) Computer simulation system for calculating the four orthogonal factors (LL, t1, Tsub and IACC) at each seat using architectural drawings were developed. The accuracy of this system were examined by comparing the calculated factors with the measured ones at Kirishima International Concert Hall. (2) The diagnostic system to measure the four orthogonal factors and additional factors (,IACCWIACC and A-value) was developed. This system can be used for the measurement in the scale model. The effect of the reflectors' array above stage which can not calculate at the design stage was evaluated at the scale model measurement of Tsuyama music cultural hall. (3) As an application of the subjective preference theory, seat selection system to maximize the preference of each individual was developed. This system, which is installed in Kirishima International Concert Hall, can find the seat where the preference is maximized by the paired comparison test with respect to the four orthogonal factors. (4) Noise measurement system to measure and identify the environment noise using the factors extracted from the autocorrelation function ( (0),e, 1 and 1) and the factors extracted from the interaural crosscorrelation function (IACC, ,IACC and WIACC) was developed. As an example, noises from different car engines were characterized by these factors measured by this system. Thesis advisor: Yoichi Ando Copies of this thesis written in English can be obtained from Masatsugu Sakurai, Yoshimasa Electronic Inc., Daiichi-Nishiwaki Bldg., 1-58-10 Yoyogi, Shibuya, Tokyo, 151-0053 Japan. E-mail address: saku@ymec.co.jp.

Acoustical Design and Measurement of a Circular Hall for Improved Spatial Factors at Each Seat

A round-shaped multi-purpose event hall (ORBIS Hall, Kobe, Japan) was designed based on the subjective-preference theory of sound fields [Y. Ando, Architectural Acoustics -Blending Sound Sources, Sound Fields, and Listeners-, AIP Press/Springer-Verlag, New York, 1998]. To avoid acoustical problems produced by round-shaped walls, and to maximize the total scale value of the subjective preference at each seat, acoustical features including several kinds of reflectors were carefully designed. The IACC calculated for the design phase, however, did not include all the installed features because these have complicated scattered reflection characteristics. After construction of the hall, therefore, the IACC measurements were conducted using two different music motifs. Results indicate that the values of the IACC are much improved due to these features. Also, the SPL-dip in the low frequency range in the area close to the stage is effectively improved by the inclusion of a perforated floor.

Acoustic design of the Tsuyama Music Cultural Hall based on the preference theory

The city of Tsuyama is located about 100 kilometers west of Kobe. The fundamental shape of the plan and cross sections of the hall were designed by applying the theory of subjective preference [Ando, Architectural Acoustics (AIP Press/Springer-Verlag, New York, 1998)]. Special attempts made in the acoustic design of this hall are: (1) a number of columns distributed in front of the walls at the audience level and on the stage: This may keep a small value of the IACC and a certain initial time delay gap between the direct sound and the first reflection, making an increase of the subjective preference for both listeners and musicians; (2) a stage enclosure with the canopy of several triangular reflectors at adjustable height for musicians, to control the preferred delay time of the reflections in performing a certain type of music; and (3) the shape of the rear wall of the stage, to control the IACC for listeners.

Design of a circular hall improving the subjective preference at each seat

The circular type of the medium-sized (400 seats) multipurpose event hall in Kobe Fashion Plaza, which was named Orvis Hall, was designed based on Ando’s theory of subjective preference. Acoustic problems caused by such a circular plan were minimized by means of ceiling diffusion panels, side-wall-reflective panels, and a small room at the back wall preventing echo-disturbance created by the long-path echo or ‘‘Whispering Gallery’’ effects. One of the most remarkable systems of this hall is controlling the subsequent reverberation time through blending architectural acoustics and electrical acoustics by use of a hybrid system with both a reverberation control room and a digital reverberator. Therefore the total scale value of subjective preference at each seat is maximized by the four acoustic factors, namely, the delay time of first reflection, the listening level, the subsequent reverberation time, and the IACC. After construction of this hall, four factors at each seat were measured, and results are presented.

Analyses of cortical continuous brain waves in relation to subjective preference of physical environments

Analyses of cortical continuous brain waves in relation to subjective preference of physical environments

REVEALED INDEPENDENCE AND QUASTILINEAR CHOICE

Revealed Independence requires that revealed preferences satisfy the independence property from expected utility theory. This condition is essentially the same as the quasi-linearity of the choice function; i.e., it is a linear operator on convex combinations of budget sets. We demonstrate the equivalence of the Strong and Weak Axioms of Revealed Preference for quasi-linear choice functions with convex domains. IN GENERAL terms, revealed preference theory derives utility from demand, complementing subjective preference theory, which derives demand from utility. This reversal of procedure has profound operational significance, because it places neoclassical economics upon a more satisfactory behavioral foundation, where all axioms become testable hypotheses about observable variables. Indeed, the utility function is unobservable to the social scientist, but the typical demand function is at least partially observable, lending itself to statistical estimation. Samuelson [15] originally developed revealed preference theory in the context of commodity markets. He unsuccessfully sought to recover the utility function from his Weak Axiom of Revealed Preference (WARP) by integrating an appropriate system of partial differential equations derived from the Hicks-Slutsky substitution matrix. This integrability problem was eventually solved by Houthakker [7], who introduced the Strong Axiom of Revealed Preference (SARP) to replace WARP. Nevertheless, a social scientist still needs a constructive procedure that verifies whether or not a particular collection of choice data satisfies these behavioral axioms. In this regard, WARP would clearly provide a much simpler foundation for consumer demand theory, and Samuelson demonstrated its sufficiency in a world with only two commodities. Unfortunately, Gale [4] constructed an important counterexample, verifying that WARP is insufficient to recover the utility function from the Marshallian demand function in general. The exact characterization of WARP and SARP in terms of the Hicks-Slutsky substitution matrix thoroughly exposes the logical distinction between WARP and SARP in the context of the neoclassical model of the competitive consumer [9]. Yet this matter is not finished for other types of decision problems. We consider here Uzawa's extension of revealed preference theory to a logical setup that encompasses social choice theory [19]. The essential step is the generalization of the concept of a demand function to a choice function,