127. A method of indexing and searching timed media files, as recited in claim 126 , wherein said analysis includes calculating the frequency of co-occurrence of at least one pair of information presentations.
127. A method of indexing and searching timed media files, as recited in claim 126 , wherein said analysis includes calculating the frequency of co-occurrence of at least one pair of information presentations. 128. A method of indexing and searching timed media files, as recited in claim 127 , wherein said model of semantic relatedness includes a measure of the mutual information, or probability of co-occurrence of the pair of information representations relative to the probability of random co-occurrence of such a pair of information representations, between the pair of information representations.