Abstract generation device, method, program, and recording medium

A summary generating method performed at a summary generating apparatus comprising a speech recognition unit, a lattice generating unit, an integer programming problem generating unit, and a summary generating unit, the method comprising:

• converting, at the speech recognition unit, an input utterance sequence into a confusion network sequence constituted by a k-best of candidate words of speech recognition results;
• generating, at the lattice generating unit, a lattice sequence having the candidate words as internal nodes and a combination of k words among the candidate words for an identical speech as an external node, in which edges are extended between internal nodes other than internal nodes included in an identical external node, from the confusion network sequence;
• generating, at the integer programming problem generating unit, an integer programming problem for selecting a path that maximizes an objective function including at least a coverage score of an important word, of paths following the internal nodes with the edges extended, in the lattice sequence;
• and
• generating, at the summary generating unit, a summary of the utterance sequence using the candidate words indicated by the internal nodes included in the path selected by solving the integer programming problem, under a constraint on a length of a summary to be generated.