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.
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. 131. A method of indexing and searching timed media files, as recited in claim 128 , wherein if a pair of information representations co-occur so infrequently that the uncertainty in the calculated mutual information relative to the calculated mutual information is above an acceptable threshold, then the frequency of co-occurrence of the pair of information representations is considered to be the frequency that would occur in a true corpus if the information representations co-occur randomly given their individual frequency of occurrence.