Dan Little: Coarse-graining of complex systems

Dan Little writes about Coarse-graining of complex systems.

I am not sure whether these debates have relevance for the modeling of social phenomena. Recall my earlier discussion of the modeling of rebellion using agent-based modeling simulations (link, link, link). These models work from the unit level — the level of the individuals who interact with each other. A coarse-graining approach would perhaps replace the individual-level description with a set of groups with homogeneous properties, and then attempt to model the likelihood of an outbreak of rebellion based on the coarse-grained level of description. Would this be feasible?

Emphasis Mine

Marxists use coarse-graining as a matter of course. We have the ideas of classes with the possibility of dividing those classes into strats.

For example, we divide a Capitalist society into two (2) major classes:

1. Capitalists
2. Workers

There are other classes, but they do not figure in the major dynamic of the class struggle between Capitalists and Workers.

The Capitalist class can be further divided into two (2) major strata:

1. Big Capitalists
2. Small Capitalists

Even though Donald Trump, Mark Cuban, Eric Schmidt, and Bill Gates have wildly different temperments, histories, world-views, and political philosophies, they have enough similarities to be lumped together as Big Capitalists. Here the coarse-graining is concentrating on those attributes that are essential to model the behaviour of a typical Big Capitalist.