Dakota Reference Manual: sub_sampling_period

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sub_sampling_period

Specify a sub-sampling of the MCMC chain

## Specification

Alias: none

Argument(s): INTEGER

Default: 0

## Description

If a `sub_sampling_period` is specified, the MCMC chain is filtered such that only the sample at the beginning of each period is in the final MCMC chain. The `sub_sampling_period` should therefore be greater than or equal to the correlation length of the samples.

Default Behavior

If not specified, all MCMC samples are included in the final chain.

Expected Output

If specified, an additional tabular output file containing the final (sub- sampled) MCMC chain is generated.

## Examples

Generate and then filter a 1000 sample MCMC chain, retainining the first accepted sample and every 100th sample thereafter.

An example method block of a Dakota input file is given below

    method,
        bayes_calibration queso
          chain_samples = 1000 seed = 348
          dram
        proposal_covariance
          diagonal values 1.0e6 1.0e-1
        sub_sampling_period 100