In the past decade, many large retail chains have gone out of business. This is commonly attributed to the advent of e-commerce, says Nathan Yang, yet that is not the only cause of mass retail closures.Blending economic theory, game theory, and data analytics, Yang and his collaborators posit that in some cases, firms’ aggressive expansion and deterrence measures are also a likely contributor. When retail chains oversaturate a market in the interest of driving competitors away, they make take on debt that’s unsustainable.