Sign-Separated Finite-Time Error Analysis of Q-Learning
- URL: http://arxiv.org/abs/2605.16103v1
- Date: Fri, 15 May 2026 15:54:35 GMT
- Title: Sign-Separated Finite-Time Error Analysis of Q-Learning
- Abstract summary: This paper develops a sign-separated finite-time error analysis for constant step-size Q-learning.<n>The analysis identifies a max-induced asymmetry in Q-learning error dynamics.
- Score: 7.8232617281369805
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: This paper develops a sign-separated finite-time error analysis for constant step-size Q-learning. Starting from the switching-system representation, the error is decomposed into its componentwise negative and positive parts. The negative part is dominated by a lower comparison linear time-invariant (LTI) system associated with a fixed optimal policy, whereas the positive part is controlled by a linear switching system. The resulting bounds show that the negative-side LTI certificate is no slower than the positive-side switching certificate and may produce a faster exponential envelope. The analysis identifies a max-induced asymmetry in Q-learning error dynamics. This asymmetry is connected to overestimation: positive action-wise errors can be selected and propagated by the Bellman maximum, whereas negative errors admit an optimal-policy lower comparison. Finite-time bounds are provided for both deterministic and stochastic constant-step-size recursions.
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