15th International Congress of Phonetic Sciences (ICPhS-15)
Existing methods for examining phonetic categorization (i.e., identification or goodness judgments) typically require listeners to give responses on every member of a stimulus set. This article describes a new method that is more efficient for higher-dimensional stimulus sets (i.e., more phonetic detail) in which the number of perceptually distinct stimuli is too large to be played within an experimental session. The method uses a traditional goodness-rating task (i.e., subjects hear individual synthesized stimuli and give goodness ratings on a continuous scale). However, the stimulus selection is determined by an iterative computer algorithm that is designed to find the minimum value of a function within a multidimensional variable space. The method has been applied to map best exemplars of English vowels in a 5- dimensional space including formant movement and duration; best exemplars can be found within the set of 100,700 possible vowels after playing subjects only 35 trials per vowel category.
Bibliographic reference. Iverson, Paul / Evans, Bronwen G. (2003): "A goodness optimization method for investigating phonetic categorization", In ICPhS-15, 2217-2220.