Yquilibrium: A Theory for (Non-) Convex Economies

General equilibrium, the cornerstone of modern economics and finance, rests on assumptions many markets do not meet. Spectrum auctions, electricity markets, and cap-and-trade programs for resource rights often feature non-convexities in preferences or production that can cause non-existence of Walrasian equilibrium and render general equilibrium vacuous. Yquilibrium complements general equilibrium with an optimization approach to (non-) convex economies that does not require perfect competition. Yquilibrium coincides with Walrasian equilibrium when the latter exists. Yquilibrium exists even if Walrasian equilibrium ceases to and produces optimal allocations subject to linear, anonymous, and (approximately) utility-clearing prices.