This writeup details BAsCET's application on bibliographic references recognition. See BAsCET for an overview.
The role of the stop agent is to avoid that the process lasts forever, by deciding to stop. Its decision is based on two principles: if the ideal solution is almost impossible to get, it is useless to continue to try to solve the problem, and if the current solution is sufficiently precise, it is useless to assign much resources to discover unnecessary details, risking to lose the already satisfying current solution, present in the Blackboard.
This agent's principle is to perform a random weighted choice: one weight for the decision "continue the treatment", and one other for "stop the treatment". The weight assigned to the continuation is fixed (10,000). On the contrary, the weight assigned to stopping depends on the Blackboard Temperature, on an idle notion, and on the time length of the already-done treatment (number of the step, or cycle).
The idle is an indicator for the number of cycles during which the agents had a null or inefficacious action (that is to say that no noteworthy change happened in the Blackboard). It is logical to say that the higher this value, the higher the reasons to stop. That means that the system does not find anything new since idle cycles, and that there is fewer chance to find anything new...
However, it turned out that the idle was not a good measure, in the sense that agents were numerous enough to find something at every cycle, and that by using only this criterion, in addition to the temperature, treatment ended only by luck (at the beginning of the cycle, the idle was 1, before that an agent "believes" to have found something new).
Also, it is clear that the more the process lasts, the more the chances that the system finds a solution diminish. Indeed, it is observed that when the number of cycles passes a threshold (depending on the application, on the size and structure of the Concept Network, and on the system's parameters) BAsCET loops: the only noteworthy actions in the Blackboard (that prevent the idle value to rise) are the deletions of structures that are built again few cycles later. Thus, to prevent the no-stopping running of the system, the current cycle number is taken into account.
See also: Building Hierarchical Structures in the Blackboard, Building the logical part of a Concept Network representing bibliographic references, Building a Concept Network to represent bibliographic references, BAsCET's application on bibliographic references recognition, BAsCET.