A stratified approach to specifying, designing, and building knowledge systems

The application of the Soar architecture to building stratified system-level models of knowledge systems is discussed. The stratified approach describes a knowledge system using three levels of computational models: the knowledge-level computational model, the problem-space computational model, and the symbol-level computational model. At the knowledge level, a system is specified in terms of the task it is to perform, the actions it can use to perform the task, and the knowledge it uses to select actions. The knowledge-level description specifies only what the system should do. How the system accomplishes the task computationally is described at the problem-space level as a hierarchy of goals and methods. The system is implemented at the symbol level in Soar using data structures and processes to implement the problem-space design.<>