A near-optimal solution is a feasible answer whose objective value lies close to the best possible value, without requiring perfect optimality. It becomes useful when exhaustive search grows too expensive, as in the traveling salesman problem. section 8.2
Approximate approaches can:
- Target a solution within a small known band of the perfect answer, such as no more than 5% less efficient. section 8.2
- Replace factorial permutation search for large traveling-salesman instances. section 8.2
- Use dynamic programming or genetic algorithms as possible strategies. section 8.2
Tour planning
For five Vermont cities, exhaustive permutation search can find a shortest 318-mile tour. With many more cities, approximation instead seeks a route close to that ideal while avoiding the rapidly expanding search space. section 8.2
Use the city map and distance table to compare a concrete optimal tour with the larger-instance motivation for near-optimal methods. section 8.2

