著者

福岡 健太 浅原 正幸 松本 裕治

出版者

一般社団法人 人工知能学会

雑誌

人工知能学会論文誌 (ISSN:13460714)

巻号頁・発行日

vol.22, no.1, pp.69-77, 2007 (Released:2007-01-05)

参考文献数

15

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Linear-chain conditional random fields are a state-of-the-art machine learner for sequential labeling tasks. Altun investigated various loss functions for linear-chain conditional random fields. Tsuboi introduced smoothing method between point-wise loss function and sequential loss function. Sarawagi proposed semi-markov conditional random fields in which variable length of observed tokens are regarded as one node in lattice function. We propose a smoothing method among several loss functions for semi-markov conditional random fields. We draw a comparison among the loss functions and smoothing rate settings in base phrase chunking and named entity recognition tasks.