# TRIBES

TRIBES is a parameter-free PSO implementation by Maurice Clerc. It combines several adaptive mechanisms to achieve good performance in different domains. It uses a dynamic number of particles, starting usually with 3 and adding new ones during optimization. Therefore, the number of generations is not directly connected to the number of fitness calls, because the population may grow (and seldomly shrink).
Also, there are different initialization methods implemented which are chosen randomly when particles are created. The particles are organized in loosely connected groups or tribes (therefore the name), creating a kind of small-world topology.
As TRIBES uses an error approximation to steer the adaptations, a target value should be given, so far in the first dimension only.