Reference · The Applied Higher-Order Functions catalogue
rainbow.algorithms.proofs.ahof.value-of-information
AHoF D19 worked value of information over signed rationals. The value of information is the signed difference EU(with info) - EU(without info). With a worked decision problem where informed expected utility is 3/4 and uninformed is 1/2, the value of information is exactly 1/4, and the worked certificates 1/2 <= 3/4 and 1/4 nonnegative are proved. That information never reduces expected utility is the classical property of the value of information and is not proved here. Signed subtraction is the addition-only Grothendieck construction, so no primitive subtraction is needed. Scope (measured by the kernel): this module has 4 worked instances (statements about specific values). None of its theorems is a guarantee about the algorithm for all inputs; `lein verify rainbow.algorithms.proofs.ahof.value-of-information` prints this classification.
ahof-d19/eu-with-info
ahof-d19/eu-with-info : → ℚ
ℚ = signed/SignedRational
ahof-d19/eu-without-info
ahof-d19/eu-without-info : → ℚ
ℚ = signed/SignedRational
ahof-d19/value-of-information
ahof-d19/value-of-information : → ℚ
ℚ = signed/SignedRational
ahof-d19/information-never-hurts
ahof-d19/information-never-hurts : → 1/2 ≤ 3/4
≤ = nnrat/at-most
ahof-d19/voi-equals-quarter
ahof-d19/voi-equals-quarter : → ahof-d19/value-of-information = signed/from-nnrat 1/4
= = signed/equivalent: equality of rational values
ahof-d19/voi-nonnegative
ahof-d19/voi-nonnegative : → signed/nonnegative ahof-d19/value-of-information
ahof-d19/value-of-information-theorem
ahof-d19/value-of-information-theorem : → proposition/conjunction (1/2 ≤ 3/4) (conjunction) where conjunction := proposition/conjunction (ahof-d19/value-of-information = signed/from-nnrat 1/4) (signed/nonnegative ahof-d19/value-of-information)
= = signed/equivalent: equality of rational values≤ = nnrat/at-most