Expectation Maximisation
نویسنده
چکیده
The Expectation Maximisation (EM) algorithm is a procedure that iteratively optimises parameters of a given model, to maximise the likelihood of observing a given (training) dataset. Assuming that our framework has unobserved data, X, observed data, Y , parameters Θ, and a likelihood function L(X,Y,Θ) = P(X,Y |Θ), we can derive the steps of the algorithm as follows: 1. Choose initial parameters, Θ0, at random. 2. (E step) Compute the expression for the expected value of the likelihood, where the unobserved data’s probability distribution is derived conditional on the observed data and current parameters:
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تاریخ انتشار 2016