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Entropy and information rate, 5 outcomes

Short answer

Entropy H = ∑ p log2(1/p) = (1/2)*1 + (1/4)*2 + (1/8)*3 + (1/16)*4 + (1/16)*4 = 1.875 bits/outcome. With 16 outcomes per second, information rate R = 16 × 1.875 = 30 bits/s.

The probability of the five possible outcomes of an experiment are given as: P(x1) = 1/2, P(x2) = 1/4, P(x3) = 1/8, P(x4) = P(x5) = 1/16. Determine the entropy and information rate if there are 16 outcomes per second.

Entropy

Probabilities: 1/2, 1/4, 1/8, 1/16, 1/16.

H = Σ pᵢ log₂(1/pᵢ) = (1/2)(1) + (1/4)(2) + (1/8)(3) + (1/16)(4) + (1/16)(4) = 0.5 + 0.5 + 0.375 + 0.25 + 0.25 = 1.875 bits/outcome

Information rate

R = r · H, with r = 16 outcomes per second:

R = 16 × 1.875 = 30 bits/s

Answer: H = 1.875 bits/outcome, R = 30 bits/second

✓ Answer checked by Claude Sonnet 5.5

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