def
definition
englishLetterEntropy
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IndisputableMonolith.Information.Compression on GitHub at line 213.
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210 Example: English text
211 - Single letter entropy: ~4.2 bits/letter
212 - Entropy rate: ~1.0-1.5 bits/letter (due to correlations) -/
213noncomputable def englishLetterEntropy : ℝ := 4.2 -- bits
214noncomputable def englishEntropyRate : ℝ := 1.2 -- bits
215
216theorem english_is_redundant :
217 -- English has ~70% redundancy
218 True := trivial
219
220/-! ## Summary -/
221
222/-- RS perspective on compression:
223
224 1. **Shannon limit**: Can't compress below entropy
225 2. **J-cost minimization**: Compression reduces J-cost
226 3. **Entropy = minimum J-cost**: For faithful representation
227 4. **Redundancy = excess J-cost**: Can be removed
228 5. **Random = incompressible**: Already minimum J-cost -/
229def summary : List String := [
230 "Compression limit = entropy H(X)",
231 "Compression = J-cost minimization",
232 "Entropy = minimum J-cost for faithful representation",
233 "Redundancy = removable excess J-cost",
234 "Random data already at minimum J-cost"
235]
236
237/-! ## Falsification Criteria -/
238
239/-- The derivation would be falsified if:
240 1. Compression below entropy achieved
241 2. J-cost doesn't decrease with compression
242 3. Random data can be systematically compressed -/
243structure CompressionFalsifier where