Log-Linear Models, MEMMs, and CRFs
نویسنده
چکیده
We have sets X and Y: we will assume that Y is a finite set. Our goal is to build a model that estimates the conditional probability p(y|x) of a label y ∈ Y given an input x ∈ X . For example, x might be a word, and y might be a candidate partof-speech (noun, verb, preposition etc.) for that word. We have a feature-vector definition φ : X × Y → Rd. We also assume a parameter vector w ∈ Rd. Given these definitions, log-linear models take the following form:
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تاریخ انتشار 2011