Kinetic energy choice in Hamiltonian/hybrid Monte Carlo
42 mins 58 secs,
625.57 MB,
MPEG-4 Video
640x360,
29.97 fps,
44100 Hz,
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About this item
| Description: |
Livingstone, S
Wednesday 5th July 2017 - 11:00 to 11:45 |
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| Created: | 2017-07-21 14:31 |
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| Collection: | Scalable inference; statistical, algorithmic, computational aspects |
| Publisher: | Isaac Newton Institute |
| Copyright: | Livingstone, S |
| Language: | eng (English) |
| Distribution: |
World
(downloadable)
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| Explicit content: | No |
| Aspect Ratio: | 16:9 |
| Screencast: | No |
| Bumper: | UCS Default |
| Trailer: | UCS Default |
| Abstract: | We consider how different choices of kinetic energy in Hamiltonian Monte Carlo affect algorithm performance. To this end, we introduce two quantities which can be easily evaluated, the composite gradient and the implicit noise. Results are established on integrator stability and geometric convergence, and we show that choices of kinetic energy that result in heavy-tailed momentum distributions can exhibit an undesirable negligible moves property, which we define. A general efficiency-robustness trade off is outlined, and implementations which rely on approximate gradients are also discussed. Two numerical studies illustrate our theoretical findings, showing that the standard choice which results in a Gaussian momentum distribution is not always optimal in terms of either robustness or efficiency. |
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| MPEG-4 Video * | 640x360 | 1.94 Mbits/sec | 625.57 MB | View | Download | |
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| iPod Video | 480x270 | 522.18 kbits/sec | 164.33 MB | View | Download | |
| MP3 | 44100 Hz | 249.74 kbits/sec | 78.68 MB | Listen | Download | |
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