A method for sequence tagging medical patient records includes providing a labeled corpus of sentences taken from a set of medical records, initializing generative parameters θ and discriminative parameters {tilde over (θ)}, providing a functional LL−C×Penalty, where LL is a log-likelihood function
where emy=1−Σ∀x<sub2>j</sub2>εV<sub2>X</sub2>p(xi|y), e{tilde over (m)}y=1−Σ∀x<sub2>i</sub2>εV<sub2>X</sub2>{tilde over (p)}(xi|y) are emission probability constraints, try=1−Σ∀y<sub2>i</sub2>εV<sub2>Y</sub2>p(yi|y), t{tilde over (r)}y=1−Σ∀y<sub2>i</sub2>εV<sub2>Y</sub2>{tilde over (p)}(yi|y) are transition probability constraints, and extracting gradients of LL−C×Penalty with respect to the transition and emission probabilities and solving θ*k,{tilde over (θ)}*k that maximize LL−C×Penalty, initializing a new iteration with θ*k,{tilde over (θ)}*k and incrementing C and repeating until solutions have converged, where parameters θ,{tilde over (θ)} are the probabilities that a new sentence X′ is labeled as Y′.