Reference · The Applied Higher-Order Functions catalogue
rainbow.algorithms.proofs.ahof.eligibility-traces
AHoF D63 worked eligibility traces (TD(lambda)) over exact rationals. With a decay factor gamma*lambda = 1/2 and a current trace 1, the visited state's trace becomes (1/2)*1 + 1 = 3/2. With learning rate 1/2, a TD error 1, and a current value 0, the trace-weighted update raises the value by (1/2)*1 to 1/2. The trace and the updated value are proved by cross-product equivalence. Scope (measured by the kernel): this module has 3 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.eligibility-traces` prints this classification.
ahof-d63/decay
ahof-d63/decay : → ℚ≥0
ℚ≥0 = nnrat/NonnegativeRational
ahof-d63/trace
ahof-d63/trace : → ℚ≥0
ℚ≥0 = nnrat/NonnegativeRational
ahof-d63/rate
ahof-d63/rate : → ℚ≥0
ℚ≥0 = nnrat/NonnegativeRational
ahof-d63/td-error
ahof-d63/td-error : → ℚ
ℚ = signed/SignedRational
ahof-d63/value
ahof-d63/value : → ℚ
ℚ = signed/SignedRational
ahof-d63/updated-trace
ahof-d63/updated-trace : → ℚ≥0
ℚ≥0 = nnrat/NonnegativeRational
ahof-d63/updated-value
ahof-d63/updated-value : → ℚ
ℚ = signed/SignedRational
ahof-d63/trace-is-three-halves
ahof-d63/trace-is-three-halves : → ahof-d63/updated-trace = 3/2
= = nnrat/equivalent: equality of rational values
ahof-d63/value-is-one-half
ahof-d63/value-is-one-half : → ahof-d63/updated-value = signed/from-nnrat 1/2
= = signed/equivalent: equality of rational values
ahof-d63/eligibility-traces
ahof-d63/eligibility-traces : → proposition/conjunction (ahof-d63/updated-trace = 3/2) (ahof-d63/updated-value = signed/from-nnrat 1/2)
= = signed/equivalent: equality of rational values