source: orange/docs/widgets/rst/evaluate/calibrationplot.rst @ 11359:8d54e79aa135

Revision 11359:8d54e79aa135, 1.7 KB checked in by Ales Erjavec <ales.erjavec@…>, 14 months ago (diff)

Cleanup of 'Widget catalog' documentation.

Fixed rst text formating, replaced dead hardcoded reference links (now using
:ref:), etc.

Line 
1.. _Calibration Plot:
2
3Calibration Plot
4================
5
6.. image:: ../icons/CalibrationPlot.png
7
8Shows the match between the classifiers' probability predictions and actual
9class probabilities.
10
11Signals
12-------
13
14Inputs:
15   - Evaluation Results (orngTest.ExperimentResults)
16      Results of classifiers' tests on data
17
18
19Outputs:
20   - None
21
22Description
23-----------
24
25Calibration plot plots the class probabilities against those predicted by
26the classifier(s).
27
28.. image:: images/CalibrationPlot.png
29
30Option :obj:`Target class` chooses the positive class. In case there are more
31than two classes, the widget considers all other classes as a single, negative
32class. If the test results contain more than one classifier, the user can
33choose which curves she or he wants to see plotted.
34
35The diagonal represents the optimal behaviour; the close the classifier gets,
36the more accurate its predictions.
37
38If :obj:`Show rug` is enable, ticks at the bottom and the top of the graph
39represents negative and positive examples (respectively). Their position
40corresponds to classifier's probability prediction and the color shows the
41classifier. On the bottom of the graph, the points to the left are those
42which are (correctly) assigned a low probability of the target class, and
43those to the right are incorrectly assigned high probabilities. On the top
44of the graph, the instances to the right are correctly assigned hight
45probabilities and vice versa.
46
47Example
48-------
49
50At the moment, the only widget which give the right type of the signal
51needed by the Calibration Plot is :ref:`Test Learners`. The Calibration Plot
52will hence always follow Test Learners and, since it has no outputs, no other
53widgets follow it. Here is a typical example.
54
55.. image:: images/ROCLiftCalibration-Schema.png
Note: See TracBrowser for help on using the repository browser.