1r.kappa(1)                    Grass User's Manual                   r.kappa(1)
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NAME

6       r.kappa   -  Calculate  error  matrix  and kappa parameter for accuracy
7       assessment of classification result.
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KEYWORDS

10       raster
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SYNOPSIS

13       r.kappa
14       r.kappa help
15       r.kappa [-wqh] classification=string reference=string   [output=string]
16       [title=string]
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18   Flags:
19       -w  wide report, 132 columns (default: 80)
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21       -q  quiet
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23       -h  no header in the report
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25   Parameters:
26       classification=string
27           File name of classification result
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29       reference=string
30           File name of reference classes
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32       output=string
33           Name of an output file containing of error matrix and kappa
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35       title=string
36           Title for error matrix and kappa Default: ACCURACY ASSESSMENT
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DESCRIPTION

39       r.kappa tabulates the error matrix of classification result by crossing
40       classified map layer with respect to reference map layer.  Both overall
41       kappa  (accompanied  by  its variance) and conditional kappa values are
42       calculated.  This analysis  program  respects  the  current  geographic
43       region and mask settings.
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45       r.kappa  calculates the error matrix of the two map layers and prepares
46       the table from which the report is to be  created.   kappa  values  for
47       overall  and each classes are computed along with their variances. Also
48       percent of commission and ommission  error,  total  correct  classified
49       result  by  pixel  counts, total area in pixel counts and percentage of
50       overall correctly classified pixels are tabulated.
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52       The report will be write to an output file which is in plain text  for‐
53       mat and named by user at prompt of running the program.
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55       The  body  of  the report is arranged in panels.  The classified result
56       map layer categories is arranged along the vertical axis of the  table,
57       while  the  reference  map  layer categories along the horizontal axis.
58       Each panel has a maximum of 5 categories (9 if wide format) across  the
59       top.   In  addition, the last column of the last panel reflects a cross
60       total of each column for each row.  All of the categories  of  the  map
61       layer  arranged along the vertical axis, i.e., the reference map layer,
62       are included in each panel.  There is a total at  the  bottom  of  each
63       column representing the sum of all the rows in that column.
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NOTES

66       It  is  recommended  to  reclassify categories of classified result map
67       layer into a more manageable number before running r.kappa on the clas‐
68       sified  raster  map  layer. Because r.kappa calculates and then reports
69       information for each and every category.
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71       NA's in output file mean non-applicable in case MASK exists.
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SEE ALSO

74       g.region, m.ipf, r.cats, r.reclass, r.report, r.stats
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AUTHOR

77       Tao Wen, University of Illinois at Urbana-Champaign, Illinois
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79       Last changed: $Date: 2006/04/13 19:01:37 $
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81       Full index
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85GRASS 6.2.2                                                         r.kappa(1)
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