A method for processing audio data, the method comprising: receiving, by a topic analysis module, speech recognition results data (401F-405F) for at least a portion of a conference recording of a conference involving a plurality of conference participants, the speech recognition results data including a plurality of speech recognition lattices with each lattice describing alternative word hypotheses for a given utterance, and the speech recognition results data also including a word recognition confidence score for each of a plurality of hypothesized words of the speech recognition lattices, the word recognition confidence score corresponding with a likelihood of a hypothesized word correctly corresponding with an actual word spoken by a conference participant during the conference; determining a primary word candidate and one or more alternative word hypotheses for each of a plurality of hypothesized words in the speech recognition lattices, the primary word candidate having a word recognition confidence score indicating a higher likelihood of correctly corresponding with the actual word spoken by the conference participant during the conference than a word recognition confidence score of any of the one or more alternative word hypotheses; calculating a term frequency metric of the primary word candidates and the alternative word hypotheses, the term frequency metric being based, at least in part, on a number of occurrences of a hypothesized word in the speech recognition lattices and the word recognition confidence score; sorting the primary word candidates and alternative word hypotheses according to the term frequency metric; including the alternative word hypotheses in an alternative hypothesis list; and re-scoring at least some hypothesized words of the speech recognition lattices according to the alternative hypothesis list. receiving, by a topic analysis module, speech recognition results data (401F-405F) for at least a portion of a conference recording of a conference involving a plurality of conference participants, the speech recognition results data including a plurality of speech recognition lattices with each lattice describing alternative word hypotheses for a given utterance, and the speech recognition results data also including a word recognition confidence score for each of a plurality of hypothesized words of the speech recognition lattices, the word recognition confidence score corresponding with a likelihood of a hypothesized word correctly corresponding with an actual word spoken by a conference participant during the conference; determining a primary word candidate and one or more alternative word hypotheses for each of a plurality of hypothesized words in the speech recognition lattices, the primary word candidate having a word recognition confidence score indicating a higher likelihood of correctly corresponding with the actual word spoken by the conference participant during the conference than a word recognition confidence score of any of the one or more alternative word hypotheses; calculating a term frequency metric of the primary word candidates and the alternative word hypotheses, the term frequency metric being based, at least in part, on a number of occurrences of a hypothesized word in the speech recognition lattices and the word recognition confidence score; sorting the primary word candidates and alternative word hypotheses according to the term frequency metric; including the alternative word hypotheses in an alternative hypothesis list; and re-scoring at least some hypothesized words of the speech recognition lattices according to the alternative hypothesis list.