[bra-ket]

check out Michael Collins's NLP course: https://www.coursera.org/course/nlangp

and notes: http://www.cs.columbia.edu/~mcollins/

he talks about averaged perceptron at the end (Lectures on generalized log-linear models - GLM http://www.cs.columbia.edu/~cs4705/)

perceptron tagger code (hw4 solution) can be found here https://github.com/emmadoraruth/Perceptron_Tagger.git