This paper proposes a new class-based m e t h o d to estimate the strength of association in word co-occurrence for the purpose of structural disambiguation. To deal with sparseness of data, we use a conceptual dictionary as the source for acquiring upper classes of the words related in t h e co-occurrence, and then use t-scores to determine a pair of classes to be employed for calculating the strength of association. We have applied our m e t h o d to determining dependency relations in Japanese and prepositional phrase attachments in English. .
