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Entropy Breakdown

The entropy module provides a detailed min-entropy assessment inspired by NIST SP 800-90B. It runs multiple estimators and reports conservative values.

Implemented in openentropy_core::conditioning.

EstimatorMethodNotes
ShannonInformation entropyClassical H = -sum p log2 p, max 8 bits/byte
MCVMost common valueConservative min-entropy estimate
CollisionCollision spacingRepetition-distance based estimate
MarkovTransition modelCaptures sequential dependence
CompressionUniversal compressionPattern recurrence estimate
t-TupleTuple frequencyRepeated tuple dominance estimate

min_entropy uses the conservative estimate used by the core report; a diagnostic floor is also available for additional caution.

GradeMin-EntropyInterpretation
A>= 6.0Excellent density for cryptographic seeding
B>= 4.0Good entropy density
C>= 2.0Moderate redundancy present
D>= 1.0High predictability risk
F< 1.0Insufficient entropy
  • --profile security for security-focused validation
  • --profile deep for broad research characterization
  • --entropy to enable entropy breakdown in custom runs