Expert Reasoning

Expert reasoning typically has special characteristics:

• Use of specialized representations appropriate to the domain and specialized problem-solving methods based on those representations.
• Translation of observables into specialized terminology and representations (e.g., ``person has turned blue'' into ``patient is cyanotic'').
• Use of empirical rules of thumb (e.g., ``to blow out a tree stump, use one stick of dynamite per 4 inches of stump diameter''[Parker, T., Rules of Thumb, Boston, MA: Houghton Mifflin Publishers, 1983.]).
• Use of empirical correlations (e.g., certain bacteria have been observed to be likely to cause infection in burn patients).
• Use of ``incidental'' facts to discriminate cases (e.g., ``a snake that swims with its head out of the water is a water moccasin''). Such discrimination depends on the sparseness of the domain (only certain snakes are possible).