Scales in spatial statistical analysis: other definitions, other fields

Dungan et al. (2002) are detailed and clear in presenting scales in the field of ecology. Observation scales, scales of ecological phenomena, and scales used in spatial statistical analysis are thoroughly explained, along with their limitations. The three categories that can utilize spatial scale are the studied phenomenon, “the spatial units or sampling units used to acquire information about the phenomenon, and the analysis of the data” (627). When addressing the definitions of phenomena, observations and analysis, we should note that “some of these definitions overlap one another or are ambiguous” (629). In particular, how would be go about determining explicit definitions? Given one of the examples in the article, what would be an explicit definition of grain? The article could have mentioned ways to gain a consensus on the aforementioned definitions. However, the authors do raise awareness of issues regarding the role of scale in spatial statistical analysis scale that have been ignored by the literature, and note that “resolution involves more than observation grain alone” (630).They further state ecologists wrongly utilize scale terminology when applying large scale use to large phenomena and small scale use to small phenomena, observations or analysis. Dungan et al.’s solution is to replace the word ‘scale’ with ‘extent’. Will such changes affect ecologist’s “arbitrary decisions” in their selection of sampling and analysis units? (638)

While the authors do indeed provide a balanced view of scale in spatial statistical analysis by delineating its advantages and limitations, I am curious about scale’s effect on other fields, beyond ecology. Dungan et al. mention that “many ecological attributes can be expected to average linearly…” (631). Although the linear outcome may work for ecologists, how will other fields that will have attributes that will result in non-linear outcomes? How will the data be analyzed? What will be the impact of the modifiable areal unit problem (MAUP)? Outside the field of ecology, complex networks are moving towards the direction of escaping the limitations of scale, where the generative models created aim to comprise of scale-free networks.

-henry miller

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