.. _sphx_glr_api_gallery_analytical_qtest:

Outlier rejection
-------------------

Dixon's Q-test and Grubbs' test for rejecting a suspect outlier from a
small data set.


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  <div id='sg-tag-list' class='sphx-glr-tag-list'></div>


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    <div class="sphx-glr-thumbnails">

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    <div class="sphx-glr-thumbcontainer" tooltip="dixon_q_test compares the gap between a suspect value and its nearest neighbor, relative to the full data range, against a tabulated critical value (~chemistrykit.analytical.systems.qtest.Q_CRITICAL_TABLE) that depends on sample size and confidence level.">

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  .. image:: /api/gallery/analytical/qtest/images/thumb/sphx_glr_plot_01_dixon_q_test_thumb.png
    :alt:

  :doc:`/api/gallery/analytical/qtest/plot_01_dixon_q_test`

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      <div class="sphx-glr-thumbnail-title">Dixon's Q-test for outlier rejection</div>
    </div>


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    <div class="sphx-glr-thumbcontainer" tooltip="grubbs_test computes G=\max_i|x_i-\bar x|/s and compares it with the critical value grubbs_critical_value, derived from Student&#x27;s t distribution so that it exists for any sample size. A Monte Carlo run on outlier-free normal data confirms that the test falsely rejects a point at the nominal rate \alpha.">

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  .. image:: /api/gallery/analytical/qtest/images/thumb/sphx_glr_plot_02_grubbs_outlier_test_thumb.png
    :alt:

  :doc:`/api/gallery/analytical/qtest/plot_02_grubbs_outlier_test`

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      <div class="sphx-glr-thumbnail-title">Grubbs' outlier test: the extreme value in standard deviations</div>
    </div>


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    </div>


.. toctree::
   :hidden:

   /api/gallery/analytical/qtest/plot_01_dixon_q_test
   /api/gallery/analytical/qtest/plot_02_grubbs_outlier_test