Reference · The Applied Higher-Order Functions catalogue
rainbow.algorithms.proofs.ahof.gae54
AHoF D54 Generalized Advantage Estimation: form a low-variance advantage estimate as an exponentially-weighted sum of one-step TD residuals; the recursive form combines the current residual with the discounted future advantage: gae-advantage delta lambda-gamma next-advantage = delta + lambda-gamma * next-advantage. A residual 1/4 with decay lambda-gamma 1/2 and future advantage 1/2 gives 1/2; the one-step (lambda-gamma 0) estimate is the residual 1/4. Values are proved by cross-product equivalence. Proved native and axiom-free. Scope (measured by the kernel): this module has 3 worked instances (statements about specific values) and 1 definitional unfoldings (true by unfolding a definition). None of its theorems is a guarantee about the algorithm for all inputs; `lein verify rainbow.algorithms.proofs.ahof.gae54` prints this classification.
gae54/gae-advantage
gae54/gae-advantage : (x₁ x₂ x₃ : ℚ≥0) → ℚ≥0
ℚ≥0 = nnrat/NonnegativeRational
gae54/recursive-estimate
gae54/recursive-estimate : → ℚ≥0
ℚ≥0 = nnrat/NonnegativeRational
gae54/one-step-estimate
gae54/one-step-estimate : → ℚ≥0
ℚ≥0 = nnrat/NonnegativeRational
gae54/gae-advantage-unfold
gae54/gae-advantage-unfold : (delta lg next : ℚ≥0) → gae54/gae-advantage delta lg next = delta + lg · next
+ = nnrat/add= = equality/Eq· = nnrat/multiplyℚ≥0 = nnrat/NonnegativeRational
gae54/recursive-is-half
gae54/recursive-is-half : → gae54/recursive-estimate = 1/2
= = nnrat/equivalent: equality of rational values
gae54/one-step-is-residual
gae54/one-step-is-residual : → gae54/one-step-estimate = 1/4
= = nnrat/equivalent: equality of rational values
gae54/gae
gae54/gae : → proposition/conjunction (gae54/recursive-estimate = 1/2) (gae54/one-step-estimate = 1/4)
= = nnrat/equivalent: equality of rational values