抄録
A new method is applied to measure the noisiness of the level-fluctuating noises exposed for a long time. The part of the stimulus to be rated is specified by light emitting diode (LED) and a subject rates the noisiness by pressing one of the category buttons. By the method, every component part of the long fluctuating noise is rated. Experimental results show that (1) the method is very effective to measure our changing impressions for a fluctuating stimulus with a long duration, (2) the part of stimulus with two to three seconds duration seems to be best for psychological judgment, (3) the method does not show the context effect which is usually found in the conventional category judgment, and (4) the noisiness value judged from the whole stimulus is much higher than the average noisiness value judged from the fractionated stimulus.
