Efficient subword lattice retrieval for German spoken term detection

Author

Mertens, Timo ; Schneider, Daniel

Author_Institution

Dept. of Electron. & Telecommun., NTNU, Trondheim

fYear

2009

fDate

19-24 April 2009

Firstpage

4885

Lastpage

4888

Abstract

We present a lattice-based STD method for German broadcast news data and compare it to a previously proposed fuzzy search. Due to the important out-of-vocabulary (OOV) problem in German, we evaluate suitable subword indexing units for lattice retrieval. Hybrid lattice retrieval of words and subwords is investigated because of the robust nature of words as an indexing unit. We show that by using efficient lattice graph and score pruning techniques, precision of subword retrieval is increased by 8% absolute with only a small loss in recall. Additionally, a speed-up of up to 6 times can be observed.

Keywords

fuzzy set theory; graph theory; indexing; information retrieval; natural language processing; speech processing; vocabulary; German spoken term detection; fuzzy search; lattice graph; lattice-based STD method; out-of-vocabulary; score pruning techniques; subword indexing; subword lattice retrieval; Broadcasting; Error analysis; Indexing; Lattices; Morphology; Natural languages; Robustness; Speech recognition; Testing; Vocabulary; speech recognition; speech search; spoken document retrieval; spoken term detection;

fLanguage

English

Publisher

ieee

Conference_Titel

Acoustics, Speech and Signal Processing, 2009. ICASSP 2009. IEEE International Conference on

Conference_Location

Taipei

ISSN

1520-6149

Print_ISBN

978-1-4244-2353-8

Electronic_ISBN

1520-6149

Type

conf

DOI

10.1109/ICASSP.2009.4960726

Filename

4960726