Alternative Forms of Bounded Suboptimal Search

Finding optimal solutions to search problems is often not practical due to run-time constraints. This has led to the development of algorithms that sacrifice solution quality in favour of a faster search. The solution quality of a suboptimal solution is often measured by the ratio C C , where C is the cost of the solution found and C is the cost of the optimal solution. Some search algorithms allow a user to define an acceptable level of solution suboptimality that any solution returned must adhere to. Such algorithms are referred to as bounded suboptimal algorithms. For example, Weighted A* (WA*) (Pohl 1970) guarantees that the ratio C C of any solution found is at most (1 + ǫ), where ǫ is the acceptable level of suboptimality defined by the user.