Geometrically Coupled Monte Carlo Sampling Mark Rowland Krzysztof - - PowerPoint PPT Presentation
Geometrically Coupled Monte Carlo Sampling Mark Rowland Krzysztof - - PowerPoint PPT Presentation
Geometrically Coupled Monte Carlo Sampling Mark Rowland Krzysztof Choromanski Franois Chalus Aldo Pacchiano Tamas Sarlos Richard E. Turner Adrian Weller Geometrically Coupled Monte Carlo Sampling Central goal: Unbiased Monte Carlo
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Geometrically Coupled Monte Carlo Sampling
Central goal: Can we do better than i.i.d.? Key contribution: K-optimality. Optimise the objective below over the joint distribution of Unbiased Monte Carlo estimation:
This leads to a multi-marginal transport problem, which is often analytically solvable.
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GCMC in Robotics - Policy Search - An Overview
isotropic distribution
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isotropic distribution
GCMC in Robotics - Policy Search - An Overview
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isotropic distribution
GCMC in Robotics - Policy Search - An Overview
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isotropic distribution
GCMC in Robotics - Policy Search - An Overview
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isotropic distribution antithetic pair
GCMC in Robotics - Policy Search - An Overview
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isotropic distribution antithetic pair
- Independent Antithetic Pairs
- Coupled Samples of Equal Lengths
Typical approach to Monte Carlo Sampling:
GCMC in Robotics - Policy Search - An Overview
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isotropic distribution antithetic pair
- Independent Antithetic Pairs
- Coupled Samples of Equal Lengths
Typical approach to Monte Carlo Sampling:
GCMC in Robotics - Policy Search - An Overview
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isotropic distribution antithetic pair
- Independent Antithetic Pairs
- Coupled Samples of Equal Lengths
Typical approach to Monte Carlo Sampling:
GCMC:
- rthogonal directions
- f different antithetic pairs
- correlated unequal lengths
within a pair
- variance reduction
GCMC in Robotics - Policy Search - An Overview
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GCMC for Policy Search - Details
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GCMC for Policy Search
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GCMC for Policy Search
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Towards smooth relaxations Gaussian smoothings
GCMC for Policy Search
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Towards smooth relaxations Gaussian smoothing gradient
GCMC for Policy Search
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Towards smooth relaxations Gaussian smoothing gradient
GCMC for Policy Search
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Baseline gradient estimator with antithetic pairs (Salimans et al. 2017):
Coupled antithetic pairs for Monte Carlo gradient estimation
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Baseline gradient estimator with antithetic pairs (Salimans et al. 2017):
Coupled antithetic pairs for Monte Carlo gradient estimation
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Baseline gradient estimator with antithetic pairs (Salimans et al. 2017): Antithetic inverse lengths coupling estimator (Rowland, Choromanski et al. 2018):
Coupled antithetic pairs for Monte Carlo gradient estimation
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Baseline gradient estimator with antithetic pairs (Salimans et al. 2017): Antithetic inverse lengths coupling estimator (Rowland, Choromanski et al. 2018):
coupled lengths coupled lengths
Coupled antithetic pairs for Monte Carlo gradient estimation
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Baseline gradient estimator with antithetic pairs (Salimans et al. 2017): Antithetic inverse lengths coupling estimator (Rowland, Choromanski et al. 2018):
coupled lengths
Coupled antithetic pairs for Monte Carlo gradient estimation
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Experimental results: Minitaur Learning How to Walk with antithetic coupled samples + linear policies
N=8 N=16 N=48 N=54 N=64 N=96
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