7th International Conference on Spoken Language Processing

September 16-20, 2002
Denver, Colorado, USA

Experiments in Confidence Scoring for Word and Sentence Verification

M. Andorno (1), P. Laface (1), Roberto Gemello (2)

(1) Politecnico di Torino, Italy; (2) LOQUENDO, Italy

The successful deployment of a telephone speech application cannot only rely on the accuracy of the recognition results, but also on their reliability. Reliable confidence measures are, thus, necessary in all practical applications to decide whether a recognized word - or sentence - should be accepted or rejected. Since most of the applications are based on continuous speech recognition, controlled by grammars, we present the results of a set of experiments aiming at assessing the quality and the limitations of different confidence measures for six different grammars that can be embedded in several applications. We show that using application independent con- fidence scoring techniques, good performance are obtained across all six grammars.

We introduce also a sentence level confidence measure that allows a significant reduction of the system error rate due to ill-formed sentences.

Full Paper

Bibliographic reference.  Andorno, M. / Laface, P. / Gemello, Roberto (2002): "Experiments in confidence scoring for word and sentence verification", In ICSLP-2002, 1377-1380.