source: orange/docs/widgets/rst/data/outliers.rst @ 11050:e3c4699ca155

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Widget docs From HTML to Sphinx.

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1.. _Outliers:
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3Outliers
4========
5
6.. image:: ../icons/Outliers.png
7
8Simple outlier detection by comparing distances between examples.
9
10Signals
11-------
12
13Inputs:
14   - Examples (ExampleTable)
15      Attribute-valued data set.
16   - Distance matrix
17      A matrix of example distances.
18
19Outputs:
20   - Outliers (ExampleTable)
21      Attribute-valued data set containing only examples that are outliers. Meta attribute Z-score is added.
22   - Inliers (ExampleTable)
23      Attribute-valued data set containing only examples that are not outliers. Meta attribute Z-score is added.
24   - Examples with Z-scores (ExampleTable)
25      Attribute-valued data set containing examples from input data with corresponding Z-scores as meta attribute.
26
27
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30Description
31-----------
32
33Outliers widget first computes distances between each pair of examples in input
34Examples. Average distance between example to its nearest examples is valued by a
35Z-score. Z-scores higher than zero denote an example that is more distant to other examples
36than average. Input can also be a distance matrix: in this case precalculated distances are used.
37
38Two parameters for Z-score calculation can be choosen: distance metrics and number of nearest examples to which
39example's average distance is computed. Also, minimum Z-score to consider an example as outlier
40can be set. Note, that higher the example's Z-score, more distant is the example from other examples.
41
42Changes are applied automatically.
43
44.. image:: images/Outliers.gif
45   :alt: Outliers
46
47Examples
48--------
49
50Below is a simple example how to use this widget. The input is fed
51directly from the `File <File.htm>`_ widget, and the output Examples with Z-score
52to the `Data Table <DataTable.htm>`_ widget.
53
54.. image:: images/Outliers-Example1.gif
55   :alt: Schema with Outliers
56
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