Selectivity in hierarchical social systems

We consider a selection process and a hierarchical institution in a dynamic model as in Harrington (1998) [4], where agents are “climbing the pyramid” in a rank-order contest based on the “up or out” policy. Agents are matched in pairs to compete, and each pair faces a particular environment. They are ranked according to the quality of their performances in this particular environment, and a fraction of the highest ranked agents are promoted. The size of this fraction characterizes the selectivity of the process, and we distinguish between local and global selectivity. We study the role of the degree of selectivity in the dynamic process where types of agent differ in their expected performances. Surprisingly, we find that an increase in the selectivity of the process can be detrimental to the agents with the highest expected performances and can increase the survivability of the lesser performing. However, if the selectivity decreases, the only survivor is the agent with the highest expected performance.