111 機械音の音質の経済評価: 音の呈示,非呈示実験間の経済評価値の比較(音色・音質の評価・設計技術(2),騒音・振動評価・改善技術)

Experiments were conducted to evaluate the economic value of the sound quality of machinery noise emitted from vacuum cleaner and hair dryer. In the experiments concerning vacuum cleaner, stimulus cards of twenty-five kinds of vacuum cleaners were presented to participants. Each card gave participants details of the characteristics of each vacuum cleaner in respect to six attributes such as manufacturer, price, noise level (dB) and sharpness (acum) of the machinery noise. In the attributes of noise level and sharpness, three levels were set up (64, 59, 54dB and 2.46, 2.21, 1.96 acum, respectively). In the explanations of these experiments, the machinery noises were not presented to participants. 50 participants evaluated their preferences for each vacuum cleaner. Rating values were applied to conjoint analysis. From the obtained partial utilities of each level in the "machinery noise" and "price" attributes, the economic valuations for a 5dB in A-weighted SPL and a 0.25 acum in sharpness were examined. The estimated values differed from those obtained in the previous study, in which the machinery noises were presented to participants in the explanation concerning the "machinery noise" attribute. In the present study, the explanations concerning the "machinery noise" attribute might affect the estimated values.