Ill-Structured Problems are problems that are not fully specified. That is, goals are incomplete, constraints are not complete, or the path to the solution is unclear.
Some common strategies to ill-structured problems:
- retrieve a known solution pattern
- start with a guess and iterate to improve it
- search among alternatives with constraints and evaluation
- forward search from the problem to the goal
- backward search from the goal to the problem
Ill-structured problems concentrate around the framing and representation. The first job is not picking a solution, but converting a messy reality to an actually solvable problem in the first place. many algorithm failures are actually formulation failures!
Well-Structured Problems are the opposite :P. They have clear goals, well-defined actions, explicit constraints, and a crisp goal set.