Relationship between Object-Based Image Analysis and Modifiable Areal Unit Problem

International audienceGEOBIA has to deal with several issues which can be considered as “burning research questions, research need and outlook” as expressed in the book edited by T. Blaschke, S. Lang and G. J. Hay in 2008 [2]. Related to quality in a general meaning, one of them is the reliability of the statistics used to find the correct objects boundaries, that finally reflects on objects comparability in a given spatial partition. Indeed, since the number of pixels can strongly change at a given scale, and due to the major advantage of GEOBIA to find objects with different size and shape, any statistical indice describing those objects must be used with a particular caution. Contrary to what is claimed in the chapter 1.4 of this book, “object-based approaches represent viable solutions to mitigate the modifiable areal unit problem (MAUP, Openshaw, 1984 [8]), since they focus analysis on meaningful geographical objects rather than arbitrary defined spatial units i.e., individual pixels” (p. 81), or “image-objects are less sensitive to MAUP than units that do not keep a correspondence with the structure of the phenomenon under study” (p. 83), GEOBIA is neither a solution to the MAUP, nor a way to reduce its effects