DENDRAL
In plain wordsA program begun at Stanford in 1965 that worked out the structure of chemical molecules from laboratory measurements using rules taken from expert chemists. It is usually called the first expert system.
A research program at Stanford University, begun in 1965, that inferred the molecular structure of organic compounds from mass-spectrometry data and other chemical evidence. A generator systematically enumerated candidate structures consistent with a molecular formula, using Joshua Lederberg's algorithm for listing possible structures, while rules encoding chemists' knowledge pruned implausible candidates and predicted the spectrum each survivor would produce, for comparison with the observed one. Its success showed that performance came mainly from specialized domain knowledge rather than from general reasoning power, the lesson that defined the expert systemexpert system, n.: A program that stores a human specialist's know-how as many if–then rules and uses them to give advice or make decisions in a narrow field, such as diagnosing infections or configuring computers. and the practice of knowledge engineering. A companion program, Meta-DENDRAL, inferred new fragmentation rules from data, an early case of machine learningmachine learning, n.: A way of building software that learns from examples instead of following rules written by a programmer. Shown thousands of labeled photos, for instance, a program can learn to recognize cats. yielding results published in the chemistry literature.
DENDRAL's designers found that adding chemistry rules mattered far more than improving the search.
Origin
Developed by Edward FeigenbaumEdward Feigenbaum, prop. n.: An American computer scientist who pioneered expert systems, programs that capture specialists' knowledge as rules to solve problems in fields such as chemistry and medicine., the geneticist Joshua Lederberg, Bruce Buchanan and the chemist Carl Djerassi, among others, in what became Stanford's Heuristic Programming Project. The name contracts 'dendritic algorithm', after the tree-shaped enumeration of candidate structures.
Related
- expert systemexpert system, n.: A program that stores a human specialist's know-how as many if–then rules and uses them to give advice or make decisions in a narrow field, such as diagnosing infections or configuring computers.
- MYCINMYCIN, prop. n.: A 1970s Stanford program that advised doctors on blood infections and antibiotics by applying hundreds of if–then rules from specialists. It performed about as well as experts but was never used on patients.
- Edward FeigenbaumEdward Feigenbaum, prop. n.: An American computer scientist who pioneered expert systems, programs that capture specialists' knowledge as rules to solve problems in fields such as chemistry and medicine.
- knowledge baseknowledge base, n.: A store of facts and rules that a program can reason with: like a database, but organized so that new conclusions can be worked out from it, not just looked up.
- symbolic AIsymbolic AI, n.: An approach to AI that writes knowledge down as human-readable symbols and rules, such as 'every bird has wings', and reasons by manipulating them step by step instead of learning patterns from data.
- heuristicheuristic, n.: A rule of thumb: a quick, usually good-enough way to make a decision or to estimate how close you are to a goal, without any guarantee of finding the best answer.
Sources
- Lindsay, R. K., Buchanan, B. G., Feigenbaum, E. A. & Lederberg, J. (1980). Applications of Artificial Intelligence for Organic Chemistry: The DENDRAL Project. New York: McGraw-Hill.
Mentioned in
AI scientistAI scientist, n.: An AI system meant to do research largely on its own: reading the literature, coming up with ideas, running experiments and writing up the results., Edward FeigenbaumEdward Feigenbaum, prop. n.: An American computer scientist who pioneered expert systems, programs that capture specialists' knowledge as rules to solve problems in fields such as chemistry and medicine., expert systemexpert system, n.: A program that stores a human specialist's know-how as many if–then rules and uses them to give advice or make decisions in a narrow field, such as diagnosing infections or configuring computers., knowledge baseknowledge base, n.: A store of facts and rules that a program can reason with: like a database, but organized so that new conclusions can be worked out from it, not just looked up., MYCINMYCIN, prop. n.: A 1970s Stanford program that advised doctors on blood infections and antibiotics by applying hundreds of if–then rules from specialists. It performed about as well as experts but was never used on patients., knowledge engineeringknowledge engineering, n.: The craft of collecting what human experts know — through interviews, observation and documents — and turning it into rules or structured data that a computer system can use.