Posterior membership

Definition taught in Mixtures and the EM algorithm, part of Statistical learning

Posterior membership

Type Definition
Taught in Mixtures and the EM algorithm
Part Statistical learning
Questions using it 4

The posterior probability that observation \mathbf{x} came from component h, evaluated at \Psi, is

\tau_h(\mathbf{x};\Psi) =\frac{\pi_h f_h(\mathbf{x};\theta_h)}{\sum_{m=1}^{H}\pi_m f_m(\mathbf{x};\theta_m)},

where \theta_h holds the mean and covariance of component h. These probabilities are the responsibilities. They are nonnegative and sum to one over h.

Used in

See also

Bayes’ rule · Posterior class probability · Bayes classifier · Mean vector and covariance matrix · Finite mixture model · Complete-data likelihood · EM for a normal mixture · Monotonicity of EM

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