cs.LGSep 16, 2026

A Convergence Framework for Deep V-Learning: Error Propagation and Sharp Action-Gap Bounds

Authors: Yury Kolomeytsev

Abstract

We establish convergence bounds for deep VV-learning with horizon HH. The algorithm fits a scalar value function to targets from executed transitions and selects actions using a predictive model and the value function. For current observed-successor targets with fresh true-kernel outcomes, the conditional mean is TβV\mathcal{T}^βV, which averages over behavior-policy actions. The Bellman optimality update is TV\mathcal{T} V. We decompose the update error into six residuals: fitting, transition reuse, target construction, replay, action selection, and exploration. Under LsL^s concentrability, their LpL^p norms (p=s/(s1)p=s/(s-1)) control expected L1L^1 policy loss. The bound explicitly weights residuals from only the last H1H-1 update blocks, plus an initialization term for shorter runs. We quantify the cost of a shared sampling distribution across horizon levels. For statistical error bounds of order nνn^{-ν}, we derive optimal continuous allocations and an integer allocation whose objective is within a factor 2ν2^ν of the constrained optimum. A margin condition with exponent αα gives action error of order Λ1+α/pΛ^{1+α/p}, where ΛΛ combines network drift and score error; a one-step construction proves the exponent sharp. Bounds on the distance between frozen and optimal scores transfer an optimal-gap condition to frozen-iterate gap bounds while retaining the mass of optimal ties. Survival probabilities and coverage conditions at deployment yield bounds for policies selected with approximate scores. Separate spatial ReLU networks per horizon level give a conditional neural regression rate, and the finite-state case gives a log-free expected fit rate. These results give expected policy-loss consistency for the fixed-horizon generative-reset approximate-ERM procedure with exact action scores and provide an explicit residual-decay criterion for FIFO/interleaved SGD.

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