<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>GRASS GIS: r.kappa</title> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> <link rel="stylesheet" href="grassdocs.css" type="text/css"> </head> <body bgcolor="white"> <img src="grass_logo.png" alt="GRASS logo"><hr align=center size=6 noshade> <h2>NAME</h2> <em><b>r.kappa</b></em> - Calculate error matrix and kappa parameter for accuracy assessment of classification result. <h2>KEYWORDS</h2> raster <h2>SYNOPSIS</h2> <b>r.kappa</b><br> <b>r.kappa help</b><br> <b>r.kappa</b> [-<b>wqh</b>] <b>classification</b>=<em>name</em> <b>reference</b>=<em>name</em> [<b>output</b>=<em>name</em>] [<b>title</b>=<em>string</em>] [--<b>verbose</b>] [--<b>quiet</b>] <h3>Flags:</h3> <DL> <DT><b>-w</b></DT> <DD>Wide report</DD> <DD>132 columns (default: 80)</DD> <DT><b>-q</b></DT> <DD>Quiet</DD> <DT><b>-h</b></DT> <DD>No header in the report</DD> <DT><b>--verbose</b></DT> <DD>Verbose module output</DD> <DT><b>--quiet</b></DT> <DD>Quiet module output</DD> </DL> <h3>Parameters:</h3> <DL> <DT><b>classification</b>=<em>name</em></DT> <DD>Name of raster map containing classification result</DD> <DT><b>reference</b>=<em>name</em></DT> <DD>Name of raster map containing reference classes</DD> <DT><b>output</b>=<em>name</em></DT> <DD>Name for output file containing error matrix and kappa</DD> <DT><b>title</b>=<em>string</em></DT> <DD>Title for error matrix and kappa</DD> <DD>Default: <em>ACCURACY ASSESSMENT</em></DD> </DL> <H2>DESCRIPTION</H2> <EM>r.kappa</EM> tabulates the error matrix of classification result by crossing classified map layer with respect to reference map layer. Both overall <EM>kappa</EM> (accompanied by its <EM>variance</EM>) and conditional <EM>kappa</EM> values are calculated. This analysis program respects the current geographic region and mask settings. <P> <EM>r.kappa</EM> calculates the error matrix of the two map layers and prepares the table from which the report is to be created. <EM>kappa</EM> values for overall and each classes are computed along with their variances. Also percent of commission and ommission error, total correct classified result by pixel counts, total area in pixel counts and percentage of overall correctly classified pixels are tabulated. <P> The report will be write to an output file which is in plain text format and named by user at prompt of running the program. <P> The body of the report is arranged in panels. The classified result map layer categories is arranged along the vertical axis of the table, while the reference map layer categories along the horizontal axis. Each panel has a maximum of 5 categories (9 if wide format) across the top. In addition, the last column of the last panel reflects a cross total of each column for each row. All of the categories of the map layer arranged along the vertical axis, i.e., the reference map layer, are included in each panel. There is a total at the bottom of each column representing the sum of all the rows in that column. <H2>NOTES</H2> It is recommended to reclassify categories of classified result map layer into a more manageable number before running <EM>r.kappa</EM> on the classified raster map layer. Because <EM>r.kappa</EM> calculates and then reports information for each and every category. <P> <EM>NA</EM>'s in output file mean non-applicable in case <EM>MASK</EM> exists. <H2>SEE ALSO</H2> <EM><A HREF="g.region.html">g.region</A></EM>, <!--<EM><A HREF="m.ipf.html">m.ipf</A></EM>,--> <EM><A HREF="r.category.html">r.category</A></EM>, <EM><A HREF="r.mask.html">r.mask</A></EM>, <EM><A HREF="r.reclass.html">r.reclass</A></EM>, <EM><A HREF="r.report.html">r.report</A></EM>, <EM><A HREF="r.stats.html">r.stats</A></EM> <H2>AUTHOR</H2> Tao Wen, University of Illinois at Urbana-Champaign, Illinois <p><i>Last changed: $Date: 2007-10-10 10:01:00 +0200 (Wed, 10 Oct 2007) $</i> <HR> <P><a href="index.html">Main index</a> - <a href="raster.html">raster index</a> - <a href="full_index.html">Full index</a></P> <P>© 2003-2008 <a href="http://grass.osgeo.org">GRASS Development Team</a></p> </body> </html>
