Teaching trade patterns and trade gains under the Ricardian trade model is one of the most difficult tasks for teachers of international economics. We propose that the utilization of both the PPF and a labor market graph makes the understanding of Ricardian trade gains much easier.

Although the one-factor Ricardian trade model with external economies of scale plays a significant role for the understanding of important trade issues under increasing returns, it lacks a compelling graphical representation. We propose a convincing graphical exposition that uses both the PPF...