What is the confidence layer?
The official DVD contains additional accuracy assessment information that is not available through the Geospatial Data Gateway in the form of an associated confidence layer. The following description of the confidence layer is taken from the document entitled ‘MDA_NLCD_User_Guide.doc’ which is available free for download with the NLCD Mapping Tool. The Confidence Layer “spatially represents the predicted confidence that is associated with that output pixel, based upon the rule(s) that were used to classify it. This is useful in that the user can see the spatial representation of distribution and magnitude of error or confidence for a given classification… This error layer represents a percent confidence associated with each rule and output categorical, classified value. It is expressed as a percentage of confidence. A value of zero would therefore have a low confidence (always wrong), while a value of 100 would have a very high confidence (always right).” For more information on the