Abstract
Current taggers assume that input texts are already tokenized, i.e. correctly segmented in tokens or high level information units that identify each individual component of the texts. This working hypothesis is unrealistic, due to the heterogeneous nature of the application texts and their sources. The greatest troubles arise when this segmentation is ambiguous. The choice of the correct segmentation alternative depends on the context, which is precisely what taggers study.
In this work, we develop a tagger able not only to decide the tag to be assigned to every token, but also to decide whether some of them form or not the same term, according to different segmentation alternatives. For this task, we design an extension of the Viterbi algorithm able to evaluate streams of tokens of different lengths over the same structure. We also compare its time and space complexities with those of the classic and iterative versions of the algorithm.
This work has been partially supported by the Spanish Government (under the projects TIC2000-0370-C02-01 and HP2001-0044), and by the Galician Government (under the project PGIDT01PXI10506PN).
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© 2002 Springer-Verlag Berlin Heidelberg
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Graña, J., Alonso, M.A., Vilares, M. (2002). A Common Solution for Tokenization and Part-of-Speech Tagging. In: Sojka, P., Kopeček, I., Pala, K. (eds) Text, Speech and Dialogue. TSD 2002. Lecture Notes in Computer Science(), vol 2448. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-46154-X_1
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DOI: https://doi.org/10.1007/3-540-46154-X_1
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