What is Double Q-Learning?

Updated May 17, 2026

Short answer

It reduces overestimation by decoupling action selection and evaluation.

Deep explanation

Two Q-functions are used: one selects actions, the other evaluates them, reducing bias.

Real-world example

Used in recommendation systems to reduce optimistic predictions.

Common mistakes

  • Using same network for both roles.

Follow-up questions

  • How many networks are used?
  • What problem does it solve?

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