Entropy Rate — Hidden Markov Model

HMM entropy rate via chain rule H = lim H(Xₙ|X₁…Xₙ₋₁). Convergence of conditional entropy estimates.

HMM Parameters

True H(hidden):
Est. H(obs):
H(obs|hidden):
Convergence Δ:
HMM entropy rate:
H = lim_{n→∞} H(Xₙ|X₁…Xₙ₋₁)
= H(X,Z) − H(Z|X) − H(Z)

Estimated via forward algorithm:
H_n = −log P(xₙ|x₁…xₙ₋₁)
Chain rule: H = avg as n→∞.

Green = running avg H̄ₙ
Orange = true Markov entropy