Discriminative Models
نویسنده
چکیده
A classic PCFG is a generative parsing model, a model of the joint probability P (x, y) of input and output. In this lecture, I will first review the distinction between generative and discriminative models (§1) and introduce the widely used log-linear models (§2). I will then discuss three different ways in which these models are used in current parsing systems: local discriminative models (§3), global discriminative models (§4), and discriminative rerankers (§5).
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