1. A construction method for a speech recognition model, comprising the steps, executed by a computer system, of: acquiring alignment between speech of each of a plurality of speakers and a transcript of the speaker; automatically joining transcripts of the respective ones of the plurality of speakers along a time axis, creating a transcript of speech of mixed speakers obtained from synthesized speech of the speakers, and replacing predetermined transcribed portions of the plurality of speakers overlapping on the time axis with a unit which represents a simultaneous speech segment; and constructing at least one of an acoustic model and a language model which make up a speech recognition model, based on the transcript of the speech of the mixed speakers.
1. A construction method for a speech recognition model, comprising the steps, executed by a computer system, of: acquiring alignment between speech of each of a plurality of speakers and a transcript of the speaker; automatically joining transcripts of the respective ones of the plurality of speakers along a time axis, creating a transcript of speech of mixed speakers obtained from synthesized speech of the speakers, and replacing predetermined transcribed portions of the plurality of speakers overlapping on the time axis with a unit which represents a simultaneous speech segment; and constructing at least one of an acoustic model and a language model which make up a speech recognition model, based on the transcript of the speech of the mixed speakers. 2. The construction method according to claim 1 , wherein the constructing step comprises a step, executed by the computer system, of defining an acoustic unit associated with a unit which represents the simultaneous speech segment and configured to represent the simultaneous speech segment, and constructing the acoustic model which makes up the speech recognition model and contains the acoustic unit.