25. A computer memory containing a word similarity data structure for determining the similarity of a pair of input words, the word similarity data structure comprising entries, each entry identifying: a semantic relation type path pattern comprising an ordered series of semantic relation types; and a weight for the semantic relation type path pattern characterizing the extent to which a semantic relation paths of the semantic relation type path pattern occurring between an arbitrary pair of words indicates that the words of the arbitrary pair have similar meanings, the word similarity data structure being usable to determine the similarity of the input words by combining the weights for semantic relation type path patterns that occur between the input words.
25. A computer memory containing a word similarity data structure for determining the similarity of a pair of input words, the word similarity data structure comprising entries, each entry identifying: a semantic relation type path pattern comprising an ordered series of semantic relation types; and a weight for the semantic relation type path pattern characterizing the extent to which a semantic relation paths of the semantic relation type path pattern occurring between an arbitrary pair of words indicates that the words of the arbitrary pair have similar meanings, the word similarity data structure being usable to determine the similarity of the input words by combining the weights for semantic relation type path patterns that occur between the input words. 27. The computer memory of claim 25 wherein the weight indicated by each entry of the word similarity data structure comprises the frequency with which the semantic relation type path pattern of the entry occurs between words known to be synonyms, reduced by the frequency with which the semantic relation type path pattern of the entry occurs between words known not to be synonyms.