Comparison Between the Inside-Outside Algorithm and the Viterbi Algorithm for Stochastic Context-Free Grammars
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چکیده
The most popular algorithms for the estimation of the probabilities of a context-free grammar are the Inside-Outside algorithm and the Viterbi algorithm, which are Maximum Likelihood approaches. The diierence between the logarithm of the likelihood of a string and the logarithm of the likelihood of the most probable parse of a string is upper bounded linearly by the length of the string and the logarithm of the number of non-terminal symbols. However, this theoretical bound is too pessimistic. For this reason, an experimental work to show the behaviour of the two functions in practical cases is necessary.
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تاریخ انتشار 1996