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Accuracy Assessment


  Primary Reference Primary &Secondary Reference Primary Reference
1985 86.45% 91.82% 0.8307
1990 85.00% 91.09% 0.8213
1995 83.55% 90.27% 0.8059
2002 82.64% 89.18% 0.7969
2006 81.91% 88.18% 0.7895
2010 82.18% 88.91% 0.7919
2015 81.82% 88.55% 0.7878


Overall Accuracy Primary Reference - The overall percent accuracy based on just the Primary Reference point. This point identifies the perceived land cover, based on reference imagery, at the center of the Landsat pixel. This is the typical accuracy reporting using ERDAS IMAGINE.

Overall Accuracy Primary & Secondary Reference - The overall percent accuracy based on combining the Primary and, if that is incorrect, the Secondary Reference points. The Secondary Reference is the next likely land cover category based on the land cover features in the immediate surrounding area.

Kappa - Expresses the proportionate reduction in error generated by a classification process compared with the error of a completely random classification. It is generally thought to be a more robust accuracy measure than simple overall accuracy calculation, since κ takes into account the agreement occurring by chance.


Error Matrices