Automated extraction of semantic content and generation of a structured document from speech

An apparatus comprising:

• identification means for identifying a probabilistic language model including a plurality of probabilistic language models associated with a plurality of concepts logically organized in a first hierarchy;
• and
• document production means for using a speech recognition decoder to apply the probabilistic language model to a spoken audio stream to produce a document including content organized into a plurality of sub-structures logically organized in a second hierarchy having a logical structure defined by a path through the first hierarchy, the document production means comprising:
• second identification means for identifying a path through the first hierarchy, comprising:
• means for identifying a plurality of paths through the first hierarchy;
• candidate production means for producing, for each of the plurality of paths P, a candidate structured document for the spoken audio stream by using the speech recognition decoder to recognize the spoken audio stream using the language models on path P;
• means for applying a metric to the plurality of candidate structured documents produced by the candidate production means to produce a plurality of fitness scores for the plurality of candidate structured documents;
• and
• means for selecting the path which produces the candidate structured document having the highest fitness score;
• and
• means for generating a document having a structure corresponding to the path identified by the second identification means.