We found in an object-based accuracy assessment of a landcover polygon map (doi:10.1080/01431161.2013.875630) that the likelihood of correct classification of patches decreases as their size decreases, slightly for large and medium-sized patches, and more dramatically for patches within two orders of magnitude of the pixel size of the input image. Whenever the correct class of a misclassified patch is shared by a correctly classified adjacent patch, the local configuration of patches will be misrepresented in addition to the local composition of classes. Therefore, if further studies confirm the abrupt decline in accuracy we observed, the suggestion by Langford et al. (2006; Ecosystems 9: 474–488) that “there is potential for large errors in nearly every landscape pattern analysis ever published” would become an understatement. Are you aware of any studies beyond Smith et al. (2002; PE&RS 68:65-70) supporting (or contradicting) this finding, and do you think that if confirmed, this would be reason enough to abandon the patch-mosaic paradigm?

NB. For those lacking institutional access, a free copy of my article “The impact of object size on the thematic accuracy of landcover maps” can be downloaded from:

http://www.tandfonline.com/eprint/nTd7ZU2h2MYZ9mnqAFWJ/full

until the download allocation (50) is exhausted. Please do not use if you can download through your institution.

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