.. _method-surrogate_based_uq: """""""""""""""""" surrogate_based_uq """""""""""""""""" Generic UQ method for constructing and interrogating a surrogate model. .. toctree:: :hidden: :maxdepth: 1 method-surrogate_based_uq-samples_on_emulator method-surrogate_based_uq-sample_type method-surrogate_based_uq-rng method-surrogate_based_uq-probability_refinement method-surrogate_based_uq-final_moments method-surrogate_based_uq-response_levels method-surrogate_based_uq-probability_levels method-surrogate_based_uq-reliability_levels method-surrogate_based_uq-gen_reliability_levels method-surrogate_based_uq-distribution method-surrogate_based_uq-variance_based_decomp method-surrogate_based_uq-diagonal_covariance method-surrogate_based_uq-full_covariance method-surrogate_based_uq-import_approx_points_file method-surrogate_based_uq-export_approx_points_file method-surrogate_based_uq-seed method-surrogate_based_uq-fixed_seed method-surrogate_based_uq-model_pointer **Specification** - *Alias:* None - *Arguments:* None **Child Keywords:** +-------------------------+--------------------+-------------------------------+---------------------------------------------+ | Required/Optional | Description of | Dakota Keyword | Dakota Keyword Description | | | Group | | | +=========================+====================+===============================+=============================================+ | Optional | `samples_on_emulator`__ | Number of samples at which to evaluate an | | | | emulator (surrogate) | +----------------------------------------------+-------------------------------+---------------------------------------------+ | Optional | `sample_type`__ | Selection of sampling strategy | +----------------------------------------------+-------------------------------+---------------------------------------------+ | Optional | `rng`__ | Selection of a random number generator | +----------------------------------------------+-------------------------------+---------------------------------------------+ | Optional | `probability_refinement`__ | Allow refinement of probability and | | | | generalized reliability results using | | | | importance sampling | +----------------------------------------------+-------------------------------+---------------------------------------------+ | Optional | `final_moments`__ | Output moments of the specified type and | | | | include them within the set of final | | | | statistics. | +----------------------------------------------+-------------------------------+---------------------------------------------+ | Optional | `response_levels`__ | Values at which to estimate desired | | | | statistics for each response | +----------------------------------------------+-------------------------------+---------------------------------------------+ | Optional | `probability_levels`__ | Specify probability levels at which to | | | | estimate the corresponding response value | +----------------------------------------------+-------------------------------+---------------------------------------------+ | Optional | `reliability_levels`__ | Specify reliability levels at which the | | | | response values will be estimated | +----------------------------------------------+-------------------------------+---------------------------------------------+ | Optional | `gen_reliability_levels`__ | Specify generalized relability levels at | | | | which to estimate the corresponding | | | | response value | +----------------------------------------------+-------------------------------+---------------------------------------------+ | Optional | `distribution`__ | Selection of cumulative or complementary | | | | cumulative functions | +----------------------------------------------+-------------------------------+---------------------------------------------+ | Optional | `variance_based_decomp`__ | Activates global sensitivity analysis based | | | | on decomposition of response variance into | | | | main, interaction, and total effects | +-------------------------+--------------------+-------------------------------+---------------------------------------------+ | Optional (Choose One) | Covariance Type | `diagonal_covariance`__ | Display only the diagonal terms of the | | | | | covariance matrix | | | +-------------------------------+---------------------------------------------+ | | | `full_covariance`__ | Display the full covariance matrix | +-------------------------+--------------------+-------------------------------+---------------------------------------------+ | Optional | `import_approx_points_file`__ | Filename for points at which to evaluate | | | | the PCE/SC surrogate | +----------------------------------------------+-------------------------------+---------------------------------------------+ | Optional | `export_approx_points_file`__ | Output file for surrogate model value | | | | evaluations | +----------------------------------------------+-------------------------------+---------------------------------------------+ | Optional | `seed`__ | Seed of the random number generator | +----------------------------------------------+-------------------------------+---------------------------------------------+ | Optional | `fixed_seed`__ | Reuses the same seed value for multiple | | | | random sampling sets | +----------------------------------------------+-------------------------------+---------------------------------------------+ | Optional | `model_pointer`__ | Identifier for model block to be used by a | | | | method | +----------------------------------------------+-------------------------------+---------------------------------------------+ .. __: method-surrogate_based_uq-samples_on_emulator.html __ method-surrogate_based_uq-sample_type.html __ method-surrogate_based_uq-rng.html __ method-surrogate_based_uq-probability_refinement.html __ method-surrogate_based_uq-final_moments.html __ method-surrogate_based_uq-response_levels.html __ method-surrogate_based_uq-probability_levels.html __ method-surrogate_based_uq-reliability_levels.html __ method-surrogate_based_uq-gen_reliability_levels.html __ method-surrogate_based_uq-distribution.html __ method-surrogate_based_uq-variance_based_decomp.html __ method-surrogate_based_uq-diagonal_covariance.html __ method-surrogate_based_uq-full_covariance.html __ method-surrogate_based_uq-import_approx_points_file.html __ method-surrogate_based_uq-export_approx_points_file.html __ method-surrogate_based_uq-seed.html __ method-surrogate_based_uq-fixed_seed.html __ method-surrogate_based_uq-model_pointer.html **Description** As surrogate models by stochastic expansion migrate into the model specification, this method provides a general-purpose UQ method to interrogate the surrogate for generating statistics. This method must identify the surrogate of interest through its ``model_pointer``, distinguishing it from fully-integrated method specifications such as :dakkw:`method-polynomial_chaos`, :dakkw:`method-stoch_collocation`, and :dakkw:`method-function_train` that couple directly with a simulation model (and form the PCE, SC, FT surrogate approximations implicitly prior to using them for generating statistics).