The HMC Algorithm with Overrelaxation and Adaptive--Step ...
The HMC Algorithm with Overrelaxation and Adaptive--Step ...
The HMC Algorithm with Overrelaxation and Adaptive--Step ...
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1.9<br />
1.7<br />
1.5<br />
1.3<br />
1.1<br />
0.9<br />
0.7<br />
0.5<br />
Background<br />
Aim of Talk<br />
<strong>The</strong> Hamiltonian Monte Carlo (<strong>HMC</strong>) <strong>Algorithm</strong><br />
Improving Performance of <strong>HMC</strong> <strong>Algorithm</strong><br />
Numerical Experiments & Results<br />
Comparing O<strong>HMC</strong> vs <strong>HMC</strong><br />
Example results from the improved <strong>HMC</strong> algorithm<br />
Gaussian Target<br />
1<br />
π(x) = exp ( − 1 (2π) n/2 |Σ| 1/2 2 xT Σ −1 x )<br />
Σ = I<br />
Results (n=64, N=2000)<br />
O<strong>HMC</strong> <strong>HMC</strong> Ideal<br />
Accept. rate 0.99 0.99 1<br />
P(0) 1.35 1.51 1<br />
κ ∗ 1.65 1.45<br />
CPU time[sec] 561.22 557.38<br />
E 0.74 0.66 1<br />
r 6.7e − 4 7.6e − 4 < 0.01<br />
τ int 1.63 1.85 0.5<br />
N eff 614 542 2000<br />
Graphical Illustration<br />
P(κ)<br />
ρ int<br />
(τ)<br />
3.1623<br />
2.5119<br />
1.9953<br />
1.5849<br />
1.2589<br />
1<br />
0.7943<br />
0.631<br />
0.5012<br />
0.3981<br />
0.3162<br />
10 −3 10 −2 10 −1 10 0 10 1<br />
κ<br />
O<strong>HMC</strong><br />
<strong>HMC</strong><br />
0.3<br />
0 2 4 6 8 10 12 14 16<br />
τ<br />
iacf O<strong>HMC</strong><br />
(τ*,τ* int<br />
) O<strong>HMC</strong><br />
iacf <strong>HMC</strong><br />
(τ*,τ* int<br />
) <strong>HMC</strong><br />
M. Alfaki, S. Subbey, <strong>and</strong> D. Haugl<strong>and</strong> <strong>The</strong> Hamiltonian Monte Carlo (<strong>HMC</strong>) <strong>Algorithm</strong>