.. _social-interaction:

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Social Interaction Analysis
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It is possible to see a circle of people with whom a person has previously been in contact. For each person from the first circle, the system determines another circle of connected people, and so on. Overall, social interaction analysis is three-circle deep.

.. important::

   The social interaction analysis is provided only when the :ref:`person recognition <persons>` is enabled.    

The social interaction analysis is available on the :guilabel:`Relations` tab. 

.. tip::
   You can also display the circle of connected people right from the :guilabel:`Persons` tab by clicking on the handshake icon.

   |persons_handshake_button_en|

   .. |persons_handshake_button_en| image:: /_static/persons_handshake_button_en.png
      :scale: 60%

   .. |persons_handshake_button_ru| image:: /_static/persons_handshake_button_ru.png
      :scale: 60%

|relations_en|

.. |relations_en| image:: /_static/relations_en.png
   :scale: 50%

.. |relations_ru| image:: /_static/relations_ru.png
   :scale: 50%

On the :guilabel:`Relations` tab, click on a person to display their first circle of relations. Keep on to unveil the entire tree of social interactions.

|circles_en|

.. |circles_en| image:: /_static/circles_en.png
   :scale: 50%

.. |circles_ru| image:: /_static/circles_ru.png
   :scale: 50%


You can apply available filters to every circle.

.. tip::
   For example, you can find older adults or people without a face mask who are directly or indirectly related to a potentially contagious person.

When searching through a circle of relations, apply the following settings:

* :guilabel:`Use the last event`: use the last event of an episode to analyze contacts between individuals. In this case, having found truly associated people is most probable as they simultaneously leave a camera’s field of view. If the option is disabled, the system will use the best event of an episode for relations search.
* :guilabel:`Relations threshold`: maximum time in seconds between the appearance of individuals to consider them related.

  |circles_settings_en|

  .. |circles_settings_en| image:: /_static/circles_settings_en.png
     :scale: 60%

  .. |circles_settings_ru| image:: /_static/circles_settings_ru.png
     :scale: 60%