Understanding and Designing Complex Systems: Response to "A framework   for optimal high-level descriptions in science and engineering---preliminary   report"
  We recount recent history behind building compact models of nonlinear, complex processes and identifying their relevant macroscopic patterns or "macrostates". We give a synopsis of computational mechanics, predictive rate-distortion theory, and the role of information measures in monitoring model complexity and predictive performance. Computational mechanics provides a method to extract the optimal minimal predictive model for a given process. Rate-distortion theory provides methods for systematically approximating such models. We end by commenting on future prospects for developing a general framework that automatically discovers optimal compact models. As a response to the manuscript cited in the title above, this brief commentary corrects potentially misleading claims about its state space compression method and places it in a broader historical setting. 
James P. Crutchfield, Ryan G. James, Sarah Marzen, Dowman P. Varn
cond-mat.stat-mech cs.AI cs.CE cs.IT math.IT nlin.CD