What Linear Models of an Economy Can Teach Us The best way to appreciate the importance of convexity in models of the economy is by a careful examination of a linear model. Because a linear model relies on von Neumann's Saddle Value Theorem, this Theorem is the starting point of the model for two reasons. First, it explains its original application to 2-person zero sum games and its use of mixed strategies. Second, it shows why mixed strategies mislead economic analysis of non convexity in production. The linear model of the economy is a valid application of the Saddle Value theorem. General Equilibrium. JEL D5