Algorithms in Computational Biology Lecture 11: Viterbi & Sampling from the Posterior
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چکیده
During the past two weeks or so, we discussed HMMs and how we can utilize them for various purposes. We developed di erent formulas and algorithms (e.g. Forward Algorithm, Backward Algorithm). Unfortunately, while doing so, we encountered an essential problem: all of these algorithms and formulas, assume that θ is known. And so, in the last two lessons, our goal was to estimate the parameters θ of the model. For this sake, we learned the EM Algorithm (or the Baum-Welch Algorithm), an iterative algorithm that is useful in exactly this case when our data is known and our parameters are hidden. Thus, we were able to solve the equation:
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تاریخ انتشار 2017