Aggregation index (Aggregation metric)
lsm_c_ai(landscape)tibble
Raster* Layer, Stack, Brick, SpatRaster (terra), stars, or a list of rasterLayers
$$AI = \Bigg[\frac{g_{ii}}{max-g_{ii}} \Bigg](100) $$
where \(g_{ii}\) is the number of like adjacencies based on the single-count method and \(max-g_{ii}\) is the classwise maximum number of like adjacencies of class i.
AI is an 'Aggregation metric'. It equals the number of like adjacencies divided by the theoretical maximum possible number of like adjacencies for that class. The metric is based on he adjacency matrix and the the single-count method.
Percent
0 <= AI <= 100
Equals 0 for maximally disaggregated and 100 for maximally aggregated classes.
McGarigal, K., SA Cushman, and E Ene. 2012. FRAGSTATS v4: Spatial Pattern Analysis Program for Categorical and Continuous Maps. Computer software program produced by the authors at the University of Massachusetts, Amherst. Available at the following web site: https://www.umass.edu/landeco/
He, H. S., DeZonia, B. E., & Mladenoff, D. J. 2000. An aggregation index (AI) to quantify spatial patterns of landscapes. Landscape ecology, 15(7), 591-601.
lsm_l_ai