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Benjamin Grimmerwith Kevin Shu and Alex L Wang

Optimizing Optimization Methods�To and Beyond Minimax Optimality

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Talk Outline

(i) Review of Minimax Optimal Methods

(ii) Beyond Minimax Optimality: A “Subgame Perfect Method”

(iii) Towards Minimax Optimal Gradient Descent

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Smooth, Convex Optimization

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Measures of Algorithms and Problem Instances

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Some History of Smooth Convex Complexity Theory

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Some History of Smooth Convex Complexity Theory

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Some History of Smooth Convex Complexity Theory

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Some History of Smooth Convex Complexity Theory

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A Sample of the History of Optimized Methods

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A Sample of the History of Optimized Methods

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A Sample of the History of Optimized Methods

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The State of Minimax Complexity Theory

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The State of Minimax Complexity Theory

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Talk Outline

(i) Review of Minimax Optimal Methods

(ii) Beyond Minimax Optimality: A “Subgame Perfect Method”

(iii) Towards Minimax Optimal Gradient Descent

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A Case of Poor Performance from OGM

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A Case of Poor Performance from OGM

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A Case of Poor Performance from OGM

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Beyond Minimax Optimality: Subgame Perfection

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Beyond Minimax Optimality: Subgame Perfection

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OGM, Perspective of [Taylor, Bach] and [Park, Park, Ryu]

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OGM, Perspective of [Taylor, Bach] and [Park, Park, Ryu]

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A Subgame Perfect Gradient Method (SPGM)

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A Subgame Perfect Gradient Method (SPGM)

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SPGM’s Subgame Perfection

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SPGM’s Subgame Perfection

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Talk Outline

(i) Review of Minimax Optimal Methods

(ii) Beyond Minimax Optimality: A “Subgame Perfect Method”

(iii) Towards Minimax Optimal Gradient Descent

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Smooth, Convex Optimization and Gradient Descent

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Conjectured Optimal Constant “Short” Steps

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Conjectured Optimal Constant “Short” Steps

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Better Theory from Long Steps (2018-2023)

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Better Theory from Long Steps (2018-2023)

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Better Theory from Long Steps (2018-2023)

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Altschuler and Parrilo’s Silver Stepsizes (2023)

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Altschuler and Parrilo’s Silver Stepsizes (2023)

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Altschuler and Parrilo’s Silver Stepsizes (2023)

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Silver Stepsizes Balance a Different s-Inequality

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Silver Stepsizes Balance a Different s-Inequality

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Composing Composable Sequences

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Composing Composable Sequences

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Examples of Basic s-Compositions and Silver Stepsizes

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Examples of Basic f-Compositions�and Recovery of Numerically Minimax Optimal Steps

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Gradient Descent’s Optimal Basic Stepsize Schedules

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Gradient Descent’s Optimal Basic Stepsize Schedules

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Talk Outline

(i) Review of Minimax Optimal Methods

(ii) Beyond Minimax Optimality: A “Subgame Perfect Method”

See Beyond Minimax Optimality: A Subgame Perfect Gradient Method

B.G., Kevin Shu, Alex L Wang arxiv:2412.06731

(iii) Towards Minimax Optimal Gradient Descent

See Composing Optimized Stepsize Schedules for Gradient Descent

B.G., Kevin Shu, Alex L Wang arxiv:2410.16249