5th International Conference on Spoken Language Processing

Sydney, Australia
November 30 - December 4, 1998

Estimation of Mental Lexicon Size with Word Familiarity Database

Shigeaki Amano, Tadahisa Kondo

NTT Basic Research Labs., Japan

A familiarity database was developed for about 80,000 Japanese words of which familiarity scores were rated by 32 Japanese adults using a 7-point scale in auditory, visual, and audio-visual modalities. Auditory, visual, and audio-visual stimulus words were selected from the database according to their word familiarity for size estimation of the mental lexicon. Sixty Japanese adults participated in a two-alternative forced-choice task (Know-Don't know) for the stimulus words. The size of the mental lexicon was estimated as the number of words of which familiarity is above a particular word corresponding to 50% point on the fitted logistic curve to "know"-response probability of the stimulus words. The estimated size was about 68,000 for auditory words, and about 66,000 both for visual and audio-visual words when homophones and homographs were included. The results suggest that very small difference in the mental lexicon size among modalities.

Full Paper

Bibliographic reference.  Amano, Shigeaki / Kondo, Tadahisa (1998): "Estimation of mental lexicon size with word familiarity database", In ICSLP-1998, paper 0015.