抄録
The present study aimed to clarify the function of 45 Japanese connectives and to examine the necessity of them in text-comprehension. Subjects were given sequences of two sentences and were asked to select connectives that were acceptable between the two sentences. Subjects were also required to rate the necessity of having connectives for each inter-sentential position. The “interchangeability” between each pair of the 45 connectives was calculated by counting the number of times that each pair was selected together for the same inter-sentential position. By using the cluster analysis based on the “interchangeability”, the connectives were classified into six clusters, i.e., “Anti-prediction”, “Confirmation”, “Causality”, “New-topic”, “Addition”, and “Disjunction”. There were some differences between our clusters and the traditional categories proposed by linguists. “Anti-prediction”, “Confirmation”, and “New-topic” were unique to our classification. Our classification seems to reflect more accurately the readers' knowledge about the use of connectives, because connectives used in the same inter-sentential situation were classified in the nearer clusters. The necessity for connectives in “Anti-prediction” and “Causality” was rated high. Without these connectives, the inter-sentential situations may impose much information processing load on readers either by upsetting their prediction in the case of “Anti-prediction”, or by requiring them to search for large amount of ‘world knowledge’ in the case of “Causality”.
