Why the λ_e penalty must tangent the Pareto curve to lift the whole frontier in RL

carlesgelada · x · 2026-09-12

Follow-up in a thread on multi-effort RL reward design: λe controls the slope of iso-reward lines in the cost-performance plane, and only when those lines are tangent to the Pareto curve is improving reward guaranteed to push the entire Pareto frontier upward.

Related event: RL Reward Design: Choosing λ_e to Lift the Whole Pareto Frontier(3 posts)→

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