How Long is the Coast of Britain? Statistical Self-Similarity and Fractional Dimension
Mandelbrot, Benoit
Science 156, no. 3775 (1967): 636-638.
“Seacoast shapes are examples of highly involved curves such that each of their portions can—in a statistical sense—be considered a reduced-scale image of the whole. This property will be referred to as “statistical self-similarity.” […] More generally, geographical curves can be considered superpositions of features of widely scattered characteristic sizes; as even finer features are taken account of, the measured total length increases, and there is usually no clear-cut gap between the realm of geography and details with which geography need not be concerned.”
Wickham, Hadley
Journal of statistical software 59 (2014): 1-23.