Structured prediction

baseNP: doesn’t contain any recursive parts.

chunking: build the tree for the sentence

Level of representation:

* Brown Corpus (level1: pos)

* Penn Trecbank (level2: sys)

* PropBank (level3: sen)

* Framenet (level4: )

All of these need lots of human labor.


h(x) = argmin(y in Y) E_(y~p(Y|X))[l(y,x,Y)]

l (y*,x,y) = 1 – delta(y,y*)

H(x) = argmax_(y in Y) Pr(y|x)

min_(h in H) E_{p}[loss(X;Y;h)] + model complexity(h)

Empirical risk = 1/N SUM_{I = 1}^{N}loss(x,y*,h)


generalized viterbi

recognize speech

wreak a nice beach

an ice beach


conditional random fields