Singapore Soundscape Site Selection Survey (S5): Identification of Characteristic Soundscapes of Singapore via Weighted k-Means Clustering

Abstract

The ecological validity of soundscape studies usually rests on the choice of soundscapes that are representative of the perceptual space under investigation. For example, a soundscape pleasantness study might investigate locations with soundscapes ranging from “pleasant” to “annoying”. The choice of soundscapes is typically researcher led, but a participant-led process can reduce selection bias and improve result reliability. Hence, we propose a robust participant-led method to pinpoint characteristic soundscapes possessing arbitrary perceptual attributes. We validate our method by identifying Singaporean soundscapes spanning the perceptual quadrants generated from the “Pleasantness” and “Eventfulness” axes of the ISO 12913-2 circumplex model of soundscape perception, as perceived by local experts. From memory and experience, 67 participants first selected locations corresponding to each perceptual quadrant in each major planning region of Singapore. We then performed weighted k-means clustering on the selected locations, with weights for each location derived from previous frequencies and durations spent in each location by each participant. Weights hence acted as proxies for participant confidence. In total, 62 locations were thereby identified as suitable locations with characteristic soundscapes for further research utilizing the ISO 12913-2 perceptual quadrants. Audio–visual recordings and acoustic characterization of the soundscapes will be made in a future study.

A Quantitative and Qualitative Experimental Framework for the Evaluation of Urban Soundscapes: Application to the City of Sidi Bou Saïd

“…Ooi et al [67] developed a model using psychoacoustic metrics to predict soundscape quality. Ooi et al [68] applied psychoacoustic analysis to characterize urban soundscapes.…”

“…In the context of our research, the respondents were divided into three main categories representing different users' interactions with the environment and perceptions. For instance, usual users of this urban environment have a perception of the sound environments strongly influenced by their knowledge of the place and habits and therefore are likely to be sensitive to unusual and/or accidental sounds, whereas people visiting the site would be more strongly inclined to perceive sounds of new cultural interest to them [28,54,68,73]. These users with a knowledge of the environment have been placed in a category with the B label.…”