.. _method-multilevel_sampling-weighted-search_model_graphs-no_recursion:

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no_recursion
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Do not recur over admissible DAGs for a given model ensemble



.. toctree::
   :hidden:
   :maxdepth: 1



**Specification**

- *Alias:* None

- *Arguments:* None


**Description**


This (default) option supports restriction to the peer DAG (all
control variates target the same truth model) in the
ACV approach (:dakkw:`method-approximate_control_variate` and
:cite:p:`GORODETSKY2020109257`) and restriction to a hierarchical
DAG (each approximation node points to the next approximation of
higher fidelity/resolution, ending with the truth model at the root
node) for weighted MLMC (:dakkw:`method-multilevel_sampling-weighted`)
and MFMC (:dakkw:`method-multifidelity_sampling`).

Note that the omission of the ``search_model_graphs`` block defaults to
no searching over either DAGs or model subsets.  The ``no_recursion`` option
exists in order to enable search over the latter while suppressing search over
the former, as shown below.




**Examples**



.. code-block::

    method,
    	model_pointer = 'ENSEMBLE'
    	approximate_control_variate acv_mf
    	  pilot_samples = 25 seed = 8674132
    	  search_model_graphs
	    no_recursion
	    model_selection
    	  max_function_evaluations = 500