PLOT_REJECT(1)

NAME
plot_reject - Plot error versus rejection rate curve for a LNKnet classifier.

SYNOPSIS
Plots error versus rejection rate curve for classifiers when patterns can be rejected and a classification decision is not required for every input pattern.

plot_reject [-pathexp directory] [-ferror file]
[-fplot file] -noutputs n [-npatterns n]
[-xmin x] [-xmax x] [-xstep x]
[-ymin x] [-ymax x] [-ystep x]
[-title string] [-verbose n] [-table_begin n]
[-table_end n] [-table_step n]
[-sum_to_one] [-mac] [-fmaclines file] [-no_graphics]

DESCRIPTION
Error rates printed out by LNKnet classifiers refer to classification accuracy when the classifier output is always used to specify a class and no patterns are rejected. This program produces a table and a plot for classifiers with continuous outputs when patterns with produce outputs below a given threshold are rejected. The plot and the table are generated using data from the error file. The error file verbosity flag verror, must be greater than or equal to 2 during testing to generate an error versus rejection rate plot. Sufficient storage capacity is required to store the error file until plot_reject is run. The plot displays the error rate versus percentage of patterns rejected and the table contains the error rate for different percentages of patterns rejected.

EXAMPLE
This example tests a Multi-Layer Perceptron classifier using test data and creates an error versus rejection rate plot.

mlp -train -create -pathdata $LNKHOME/data/class \
-finput vowel.train -fdescribe vowel.defaults \
-npatterns 338 -fparam mlp.param -nodes 2,25,10 -epochs 100

mlp -pathdata $LNKHOME/data/class -finput vowel.test \
-fdescribe vowel.defaults -npatterns 167 \
-ferror mlp.err.test -verror 2 -fparam mlp.param

plot_reject -pathexp ./ -ferror mlp.err.test \
-fplot reject.plot -noutputs 10

OPTIONS

--  Prints a list of all flags and arguments.

-pathexp directory
    Directory where ferror and fplot are stored.

-ferror file
    File where the trial-by-trial classification test results are stored. The error file verbosity flag verror, must be greater than or equal to 2 during testing to generate this error file.

-fplot file
    File for storing plot.

-noutputs n
    There are outputs for n classes stored in the error file.

-npatterns n
    Read results for the first n patterns from the error file. If -npatterns is set to 0, read all the patterns in the file.

-xmin x
    The lower limit of the percent rejections axis for the plot.

-xmax x
    The upper limit of the percent rejections axis for the plot.

-xstep x
    The space between tic marks on percent rejections axis for the plot.

-ymin x
    The lower limit of the percent error axis for the plot.

-ymax x
    The upper limit of the percent error axis for the plot.

-ystep x
    The space between tic marks on the percent error axis for the plot.

-title string
    Title for plot.

-verbose n
    Controls amount of printout.

    0 - Nothing printed to standard output

    1 - Print a sampled table to standard output using the table_begin, table_end and table_step arguments to determine which entries to put in the table.

    2 - Print a table containing all the points in the plot to standard output.

-table_begin n
    When the verbosity is 2, percentage patterns rejected for first line of table (defaults to 0).

-table_end n
    Percentage patterns rejected for last line of table (defaults to 100.0).

-table_step n
    Increment in percentage patterns rejected in table (defaults to 2.0).

-sum_to_one
    Normalize the outputs for each pattern to sum to one before sorting them to generate the plot.

-mac
    If this flag is set, the points in the plot will be written to the file -fmaclines.

-fmaclines file
    This is an ASCII file containing the data used to create the error versus rejection rate plot. Each line contains the percentage of patterns rejected followed by the percent error rate. This file can be used to generate plots on a MacIntosh or other PC using a spread-sheet graphing program such as Excel or DeltaGraph.

-no_graphics
    Generate the plot file but do not display it in an olxplot window.

SEE ALSO
classifier(1), gauss_lnk(1), gmix_lnk(1), irbf_lnk(1), rbf_lnk(1), mlp_lnk(1), histogram_lnk(1), parzen_lnk(1)

HISTORY
First written July 1993.
Modified 19 April 1995, added noutputs and no_graphics.

BUGS
Send bug reports to Linda Kukolich (kukolich@sst.ll.mit.edu)