In our experimental design, we use four different surplus configurations. Each surplus configuration represents a different matching market. We vary the configurations in two dimensions: (1) whether the stable matching pattern is assortative, and (2) whether equal split is in the core. We also design the surpluses in a way that the maximum total surplus that all agents can obtain is 200, the average total surplus that all agents can obtain is 180 if they are all matched randomly, and the minimum total surplus they can obtain is 160, which is constant across all four markets. Maximum total surplus is obtained only under stable matching. Hence, the rate of stable matching serves as a measure of efficiency.
We employ a within-subject treatment design. All the subjects play the four different matching markets (surplus configurations), but they play them in different orders. According to the Latin square method, we have in total four different treatment, which differ in the order of markets played by the subjects. The four treatments orders are described below.
1. Positive assortative, negative assortative, mixed equal, mixed nonequal.
2. mixed nonequal, positive assortative, negative assortative, mixed equal.
3. Mixed equal, mixed nonequal, positive assortative, negative assortative.
4. Negative assortative, mixed equal, mixed nonequal, positive assortative.