Identify a target estimand under the model
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Based on the causal graph, DoWhy finds all possible ways of identifying a desired causal effect based on
the graphical model. It uses graph-based criteria and do-calculus to find
potential ways find expressions that can identify the causal effect. 

Supported identification criteria
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

* Back-door criterion
* Front-door criterion
* Instrumental Variables
* Mediation (Direct and indirect effect identification)

Different notebooks illustrate how to use these identification criteria. Check
out the `Simple Backdoor <https://github.com/microsoft/dowhy/blob/master/docs/source/example_notebooks/dowhy_confounder_example.ipynb>`_ notebook for the back-door criterion, and the `Simple IV <https://github.com/microsoft/dowhy/blob/master/docs/source/example_notebooks/dowhy-simple-iv-example.ipynb>`_ notebook for the instrumental variable criterion.

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