GC: n
CT: How the inference engine works. In simple rule-based systems, there are two kinds of inference, forward chaining and backward chaining.
Forward chaining: data gets put into working memory. This triggers rules whose conditions match the new data. These rules then perform their actions. The actions may add new data to memory, thus triggering more rules. And so on. This is also called data-directed inference, because inference is triggered by the arrival of new data in working memory.
Backward chaining: the system needs to know the value of a piece of data. It searches for rules whose conclusions mention this data. Before it can use the rules, it must test their conditions. This may entail discovering the value of more pieces of data, and so on. This is also called goal-directed inference, or hypothesis driven, because inferences are not performed until the system is made to prove a particular goal (i.e. a question).
S: http://www.j-paine.org/students/lectures/lect3/node10.html (last access: 23 December 2014)
N: 1. inference (n): 1590s, from Medieval Latin inferentia, from Latin inferentem (nominative inferens), present participle of inferre (see infer).
engine (n): c.1300, “mechanical device,” especially one used in war; “manner of construction,” also “skill, craft, innate ability; deceitfulness, trickery,” from Old French engin “skill, wit, cleverness,” also “trick, deceit, stratagem; war machine” (12c.), from Latin ingenium “inborn qualities, talent” (see ingenious), in Late Latin “a war engine, battering ram” (Tertullian, Isidore of Seville). Sense of “device that converts energy to mechanical power” is 18c.; in 19c. especially of steam engines.
2. That part of a knowledge-based system or expert system that contains either specific or general problem-solving knowledge.
3. The inference engine processes the domain knowledge (located in the knowledge base) to solve problems, reach solutions, or lead to further steps.
4. inference engine: term standardized by CSA International in 1992 and ISO/IEC in 1995.
5. In order to accomplish feats of apparent intelligence, an expert system relies on two components: a knowledge base and an inference engine. A knowledge base is an organized collection of facts about the system’s domain. An inference engine interprets and evaluates the facts in the knowledge base in order to provide an answer.
S: 1. OED – http://www.etymonline.com/index.php?allowed_in_frame=0&search=inference&searchmode=none; http://www.etymonline.com/index.php?allowed_in_frame=0&search=engine&searchmode=none (last access: 23 December 2014). 2, 3 & 4. TERMIUMPLUS. 5. EncBrit – http://global.britannica.com/EBchecked/topic/287556/inference-engine (last access: 23 December 2014).
SYN: 1. inference machine. 2. inference mechanism, inference move.
S: 1. GDT ; TERMIUMPLUS. 2. TERMIUMPLUS.
CR: artificial intelligence, automatic control engineering, computer science, expert system, ontology, robotics.
