I

I

SUBJECT INDEX

Ablation studies, of HARPY, 335Abstraction space, in ABSTRIPS, 136ABSTRIPS, 22, 28, 134, 135-130, 160Acoustics, 343Acquisition of knowledge. See Knowledge

acquisition.ACT, 105Active structural network, 185. See also

Semantic network.Ad hoc knowledge representation, 227Ad hoc parsers, 287Adaptive production system, 105Add list

in ABSTRIPS, 135in STRIPS, 128-134

Admissibilityof A*, 65of ordered search, 80, 83of shortfall density strategy, 341, 356

Admissibility condition, 65, 67, 73Agenda, 338, 356, 360. See also Control

strategy.Agreement, in natural language, 263AI programming languages, 10, 172, 175.

See also Knowledge representationlanguages.

CONNIVER, 175, 176INTERLISP, 320EPL-V, 281-282LISP, 15, 173, 237, 283, 205, 303list processing, 227, 281-287MICRO-PLANNER, 205-207PLANNER, 151, 155, 171, 175-178,

205-207POPLER, 176QA3, 129, 168, 169QA4, 176QLISP, 176SLEP, 286

ALGOL, 237A* algorithm, 64-73, 80Allophone, 333, 337, 340Alpha-beta pruning of game trees, 88-93,

94, 101AM, 157, 105-197Ambiguity

in natural language, 208-211in speech, 325-327

Analogical knowledge representation. SeeDirect (analogical) knowledgerepresentation.

Analogical reasoning, 146Anaphoric reference, 293, 358AND/OR graph, 26, 38-40, 43, 74, 113,

119, 124. See also Problem repre-sentation,

generalized, 82search of, 54-57, 74-83

AND/OR tree, 39, 56, 94, 268. See alsoProblem; representation,

context tree, 197degree of, 91game tree, 25, 43-45, 84solution tree, 40, 75, 77-79transition tree, 316-317

Application language, in LEFER, 316Applications of AI. See also Games;

Puzzles,chemistry, 168document retrieval, 328, 351education, 186expert systems, 9geometry, 119-122, 201-202information retrieval, 22, 282, 283, 292,

316, 318machine translation, 207-213, 225, 226,

233-238, 273, 274, 270, 281, 288-201mathematics, 105

Subject Index396

Applications of AI {continued)medicine, 105, 220paraphrasing, 140, 211, 255, 274,

302-304, 321question answering, 168-160, 173,

185-186, 281, 205, 302science, 221space planning, 202story understanding, 231, 300, 306symbolic integration, 21, 22, 24, 118,

123-127travel budget manager, 353voice chess, 328, 334, 344

ARPA speech understanding research(SUR), 327, 353

Augmented transition network (ATN),186, 230, 261, 263-267. See alsoGrammar; Parsing,

in GSP, 268, 271in LEFER, 316in LUNAR, 202-204in MARGIE, 303, 304in speech understanding systems, 350,

355in text generation systems, 277-270

Automatic programming, 0Average branching factor. See Branching

factor.Axiomatic system, 165

Babel, 278Backed-up values, in game trees, 87Backgammon, 103Backtracking control strategy, 23, 138,

203, 258, 266, 271, 208, 330, 341, 351Backward-chaining control strategy, 105,

108Backward reasoning, 23-25, 36, 51, 56,

74, 110, 111. See also Controlstrategy; Expectation-drivenprocessing; Top-down processing.

Bandwidth condition, 60Bandwidth search, 60, 60-71Bare template, 288, 200BASEBALL, 227, 237, 282Beam search, 337, 341, 350, 356Beam width, 341Best-first search, 50, 60, 102, 360Bidirectional search, 24, 51-53, 72-73, 74Blackboard, 107, 331, 336, 343-346. See

also Control strategy; Knowledgesource.

Blind search, 21, 20-30, 46-57

bidirectional, 72and heuristic search, 58and ordered search, 61-62in Logic Theorist, 111

Blocks world, 276Bottom-up processing. See also Control

strategy; Data-driven processing;Forward reasoning,

definition of, 23-24in production systems, 108in natural-language parsing, 250, 270in speech understanding, 326, 334, 338,

358Branch-and-bound, 64Branching factor

average, in speech system grammars,328-320

of a search tree, 01, 08Breadth-first search, 47-48, 56-57, 61, 68,

73, 111

Caps, ioe, ioeCase ambiguity, 201Case frame, 182, 186, 231, 253Case grammar, 220, 240, 252-255, 277Causal chain, 301Chart, 260, 268-271, 354Checkers, 26, 43, 44, 05, 07Chemistry, applications of AI in, 168Chess, 6, 22, 23, 26, 43, 04-108, 205,

334, 351Co-routining, 271. See also Control

strategy; Parallel processing.Combinatorial explosion, 27, 28, 58, 08,

00, 154, 155, 168, 260, 330, 356Competence vs. performance, 245Compiled knowledge, 336-337, 340Completeness, of a knowledge

representation, 178Computational linguistics, 226, 220, 233,

304Computer-assisted instruction, 186Conceptual analyzer, in MARGIE, 303Conceptual dependency theory (CD)

in MARGIE, 300-303in SAM and PAM, 306and semantic primitives, 211-215, 231and text generation, 278-270

Conceptualization, 213Concordance, 226Conflict resolution, in production systems,

102, 107Conjunctive subgoals, 111, 110

Subject Index 397

Connected-speech understanding. SeeSpeech understanding.

CONNIVER, 175-176Consistency assumption, in search

algorithms, 66, 60, 73Consistency, of a knowledge

representation, 178Constraining knowledge, 344Constraint-structured planning, 203Construction, in geometry, 121Context

in production systems, 100, 107in speech understanding, 333

Context tree, in MYCIN, 107Context-free grammar. See also Phrase-

structure grammar,definition of, 242-243in parsing, 260, 263in text-generation, 273-274in transformational grammar, 247

Context-sensitive grammar, 241-242. Seealso Phrase-structure grammar.

Control strategy. See also Problem solv-ing; Reasoning; Search algorithms,

agenda, 338, 356, 360backtracking, 23, 138, 203, 258, 266,

271, 208, 330, 341, 351backward chaining, 105, 108blackboard, 107, 331, 336, 343-346bottom-up, 23-24, 108, 220, 250, 270,

326, 334, 338, 358Co-routining, 271conflict resolution, 102, 107data- or event-driven, 24, 108, 220definition of, 22demons, 303direction of, 23-24, 108, 220event queue, 356expectation- or goal-driven, 183, 108,

216-218, 232, 326, 334, 336, 344focus of attention, 100, 107, 338, 340,

347, 356, 360forward chaining, 108hybrid, 340, 356hypothesis posting, 336, 338, 354island driving, 250, 337, 330, 346, 356,

361matching, 150, 187parallel processing, 258, 265, 208in parsing, 230, 258-250in PLANNER, 170procedural attachment, 156, 158, 170,

218-221

and procedural knowledge represen-tation, 174

in production systems, 104, 107-108in speech systems, 336-342, 347,

350-351, 355-357, 350-360scheduler, 347, 356top-down, 183, 108, 216-218, 232, 250,

326, 334, 336, 338, 344, 355, 358, 350CONVERSE, 228Cost, in search algorithms, 75-77Critical node, in a game tree, 01Criticality value, in ABSTRIPS, 136CRYSALIS, 336Cybernetics, 4, 233

Data-driven processing, 23-24, 108,220. See also Bottom-up processing;Con- trol strategy; Forwardreasoning.

Database, 22, 328. See also Informationretrieval.

DEACON, 228Dead position, in a game, 87, 00Declarative knowledge representation, 230

vs. procedural knowledge representa-tion, 151, 172, 210

Deduction, 146, 205. See also Inference;Reasoning.

Deep structure, in language, 247, 266Default reasoning, 176-177Default values, 183, 216-220Degree of a tree, 01Delete list

in ABSTRIPS, 135in STRIPS, 128

Demon, 303. See also Control strategy.DENDRAL, 60, 157, 198Denotative knowledge representation, 200Dependency grammar, 274Depth bound, 40, 57, 00, 115Depth-first search, 40-51, 57, 60, 61, 101,

113, 138, 203Depth of a node, 40Derivation tree, 220, 242, 246, 256, 266,

273, 281, 203, 206, 302Diagram, reasoning from, 201Dialogue. See Discourse.Dictionary, for machine translation, 234Difference

in GPS, 113in means-ends anaylsis, 24in STRIPS, 120

Subject Index398

Direct (analogical) knowledge represen-tation, 158, 177, 200-206

and parallel processing, 204vs. propositional knowledge represen-

tation, 200Directedness of reasoning, 151, 174-177,

185, 188, 103, 210Direction of reasoning, 23-24, 108, 250Discourse, 330, 358

dialogue, 220extended, 270pragmatics, 240, 327, 332, 334, 350

Discovery, by AM, 106Discrimination network, 158, 278, 304Distributed processing, 336. See also

Parallel processing.Divide-and-conquer. See Problem

reduction.Document retrieval task, 328, 351Domain-specific knowledge, 151, 176, 220.

See also Heuristic.DRAGON, 328-320, 337Dynamic ordering, 102Dynamic programming, 351Dynamic weighting, 60

Early natural language programs,227-220, 237, 257, 260, 281-287

Education, applications of AI in, 1868-puzzle, 32, 51, 62, 67, 68Elimination rule, in logic, 163, 164, 160ELIZA, 227, 257, 260, 285-287Ellipsis, in natural language, 320, 358Embedding, in natural language, 263EPAM, 158, 106Epistemology, 151, 153, 170Evaluation function, 60, 61-62, 64, 67-73,

77, 78, 80, 83, 07Event-driven processing. See Data-driven

processing.Event queue, 356Expansion of a node, 46, 55Expectation-driven processing, 183, 108,

216-218, 232, 326, 334, 336, 344.See also Backward reasoning; Controlstrategy; Top-down processing.

Expert system, 0explanation by, 0, 105, 108-100knowledge-based system, 227, 220knowledge engineering, 0, 108

Expertise, interactive transfer of, 100Explanation, by expert systems, 0, 105,

108-100

Explicit vs. implicit knowledge repre-sentation, 150, 172

Extended discourse, 270Extended grammar, 245-255Extended grammar parsers, 260Extended inference, 176

15-puzzle, 68, 73Finite-state grammar, 337. See also

Regular grammar.Finite-state transition diagram (FSTD),

263-264First-order logic, 165Fixed ordering of nodes, in search, 90,

101Focus of attention, control strategy, 190,

197, 338, 340, 347, 356, 360FOL, 169, 171, 205Formal grammar, 230-244Formal language, 230-244, 263Formal reasoning, 146Formula, in preference semantics, 288-280Forward-chaining control strategy, 108Forward pruning, of game trees, 104Forward reasoning, 23-25, 51, 56, 74, 108Frame knowledge representation, 140,

156, 158-150, 216-222, 334-335. Seealso Script knowledge representation,

and case frames, 183, 254matching in, 150and preference semantics, 208, 220, 231and semantic networks, 183, 186, 180

Frame problem, 177, 201Fregean knowledge representation. See

Propositional knowledge represen-tation.

FRL-0, 221Full-width search, 103Functions, in logic, 165

Game tree, 25, 43-45, 84random, 02totally dependent, 02uniform, 01-03

Game-tree search, 84-108. See alsoSearch algorithms; AND/OR tree,

alpha-beta, 88-03, 04, 101backed-up values, 87dead position, 87, 00forward, 104horizon effect, 00killer heuristic, 102live position, 87

Subject Index 399

method of analogies, 104minimax, 84-87, 88, 90, 91, 94, 98negmax, 86-87, 89plausible-move generation, 104quiescence, 99-100, 103refutation move, 102secondary search, 100static evaluation function, 87, 96-97,

100tapered forward, 104

Games, 153. See also Puzzles,backgammon, 103checkers, 26, 43, 44, 95, 97chess, 6, 22, 23, 26, 43, 94-108, 205,

334, 351go, 103tic-tac-toe, 43, 04voice chess, 328, 334, 344

General Problem Solver (GPS), 113-118,120, 135, 160, 106. See also Means-ends analysis.

General Space Planner, 202-203General Syntactic Processor (GSP),

268-272Generality vs. power, 335Generalized AND/OR graph, 82Generate-and-test, 30Generative grammar, 220, 245, 247Generative semantics, 248Geometry Theorem Prover, 110-122,

201-202Go, 103Goal, 22, 36, 105, 114, 306, 308, 310-311Goal-directed reasoning. See Backward

reasoning; Control strategy;Expectation-driven processing; Top-down reasoning.

Goal states, 33GOLUX, 171, 175GPS. See General Problem Solver.Graceful degradation, 336Grain size of a knowledge representation,

147Grammar. See also Natural language

understanding; Parsing.ATN, 186, 230, 261, 263-267, 268, 271,

277-270, 202-204, 303, 304, 316average branching factor of, 328, 320case, 220, 240, 252-255, 277context-free, 242-243, 245, 247, 260,

263, 273, 274context-sensitive, 241-242, 245definition of, 225, 220

dependency, 274extended, 260-261finite-state, 337formal, 230-244generative, 220, 245, 247habitability of, 328mood system of, 240obligatory and optional transformations

in, 247and parsing, 256, 260-262performance, 261, 335, 355, 350phrase-structure, 240-246, 260, 262regular, 243, 245, 263semantic, 220, 261, 318, 320, 335, 355,

350in speech systems, 326, 332, 340story, 306systemic, 220, 240-251, 207transformational, 220, 233, 237, 245-

-248, 240, 251, 252transition tree, in LIFER, 316-317transitivity system of, 240

Grammarless parsers, 261Graph Traverser, 67Ground space, in ABSTRIPS, 135GSP. See General Syntactic Processor.GUS, 220, 231

Habitability of a language, 328HAM, 185HARPY, 328, 320, 335, 337, 330, 344,

346, 340-352, 356HAWKEYS, 318HEARSAY, 106-107, 336, 338, 343-348

HEARSAY-I, 328, 334, 335, 343HEARSAY-H, 328, 345

Heuristic, 21, 64, 66, 74, 78, 04, 110, 151,168, 174, 177, 188, 201, 220, 228,258, 277, 282, 284, 203, 206, 208,200, 335. See also Heuristic search.

definitions of, 28-30, 58, 100killer, in game playing, 102

Heuristic Path Algorithm, 67Heuristic search, 28, 20-30, 46, 58-83,

04-108, 117, 350, 356Hierarchical planning, 135Hierarchical search, 135Hierarchy. See Inheritance.Homomorphic knowledge representation,

200Horizon effect, in game-tree search, 00Human engineering, 310Human memory. See Memory, models of.

Subject Index400

Human problem solving, 6-7, 14, 285HWIM, 267, 202, 328, 337, 330, 353-357Hybrid control strategy, 340, 356Hypothesis posting, 336, 338, 354. See

also Control strategy.Hypothesis scoring, 340, 346, 347, 351,

355, 356shortfall density strategy, 341, 356uniform scoring policy, 340

Hypothesize-and-test. See Generate-and-test.

Hypothetical worlds, 360

Ideational function of language, 240Incremental simulation, in HWIM, 341Indeterminacy of knowledge represen-

tations, 148Inexact reasoning, 105Inference, 146, 188, 213, 228, 231, 236-

-237, 255, 276, 303-304. See alsoReasoning,

extended, 176rules of, 146, 154, 155, 160, 162-165,

168, 175Information retrieval, 22, 145, 282-283,

202, 316, 318Information-processing psychology. See

Psychology.Informedness of an algorithm, 65Inheritance

hierarchy, 156, 181, 218of properties, 156, 181-184, 216, 218

Initial states, 33Instance, in semantic networks, 182Integration. See Symbolic integration.Intelligence, 3-11Intelligent technology, 3Interactive transfer of expertise, 100Interdependent subproblems, 56, 81-83Interlingua, 234-235, 237, 288, 300, 303,

304INTERLISP, 320Intermediate OR node, 30, 56, 57Interpersonal function, of language, 240Interpreter, of a production system,

100-102Interpretive semantics, 248Intonation, in speech signal, 333Introduction rule, in logic, 163, 164, 160IPL-V, 281-282Island-driving control strategy, 250, 337,

330, 346, 356, 361

Isolated-word recognition of speech, 325,333, 340

Iterative deepening search, 100-101

Juncture rules, in speechunderstanding, 330, 350, 354

Killer heuristic, 102Kinship relations, 281KLONE, 221Knowledge, 144. See also Heuristic,

compiled, 336, 337, 340compiler, 349constraining, 344domain-specific, 151, 176, 220explicit vs. implicit, 150, 172world, 226, 230

Knowledge acquisition, 145, 104, 105, 108See also Learning.

Knowledge-based system, 227, 220. Seealso Expert system.

Knowledge engineering, 0, 108. See alsoExpert system.

Knowledge representation, 143-222, 226,229-232. See also Knowledge repre-sentation languages,

ad hoc, 227completeness of, 178consistency of, 178declarative, 230declarative vs. procedural, 151, 172,

219, 230denotative, 200direct (analogical), 158, 177, 200-206homomorphic, 200indeterminacy of, 148issues in, 145-152modularity of, 149, 157, 170, 178, 193,

198, 336, 343organization of, 336procedural, 146, 149-150, 155-156,

172-179, 219-220, 230, 289, 295-297procedural-declarative controversy, 151,

230propositional (Fregean), 200propositional vs. direct, 200scope of, 147semantic interpretation function, 200

Knowledge representation languages. Seealso AI programming languages.

FRL-0, 221KLONE, 221KRL, 158, 221, 231

Subject Index 401

UNITS, 221Knowledge source, 257, 208, 326, 336,

343-348, 353. See also Blackboard.ablation studies of, 335response frame of, 345, 347stimulus frame of, 345

KRL, 158, 221, 231

Ladder, 318Language definition system, 316, 359Language, formal, 239-244, 263Language understanding. See Natural

language understanding.Learning, 9, 97, 128, 145, 157, 193, 195.

See also Knowledge acquisition.Legal-move generator, 153, 334, 344Length-first search, 138Lexicon, 247, 333, 346, 354LIFER, 231, 232, 261, 316-321, 360Limited-logic natural language systems,

228Linguistics, computational. See

Computational linguistics.LISP, 15, 173, 237, 283, 295, 303List processing, 227, 281-287Live position in a game, 87Logic, 4, 8, 146, 148, 151, 154-155,

160-171, 172, 174completeness and consistency of, 178first-order, 165functions in, 165natural deduction in, 163, 164, 169,

175predicate calculus, 128, 163, 200, 292,

297, 299predicates in, 163, 182propositional calculus, 109, 116, 118,

160-163quantification in, 151, 164, 360resolution method in, 168, 175

Logic Theorist (LT), 24, 109-112, 113,116, 119

LUNAR, 230, 267, 292-294, 353

Machine translationcurrent status of, 237-238early AI work in, 226, 233-237and semantic primitives, 207-213and text generation, 273-274, 279, 289,

291Wilks's system, 288-291

Machinese. See Interlingua.Macro-operators, 28

MACROP, 133Manageability, of production systems,

193, 198MARGIE, 149, 211, 231, 278, 300-305,

306, 334Matching. See also Control strategy,

Pattern matching,of frames, 159of semantic network fragments, 187

Mathematics, applications of AI in, 195Max cost. See Cost, in search algo-

rithms.Means-ends analysis, 24, 50, 113, 117,

126, 120, 135, 160. See also GeneralProblem Solver.

Mechanical translation. See Machinetranslation.

Medicine, applications of AI in, 105, 220MEMOD, 215Memory, models of. See also Psychology;

Semantic network knowledge repre-sentation.

ACT, 195associative, 230

EPAM, 158, 106HAM, 185imagery, 201MEMOD, 215Quillian's spreading activation system,

185, 187semantic network, 180

Meta-knowledge, 144, 147Method of analogies, in game-tree search,

104MICRO-PLANNER, 205-207Middle-out search strategy. See Island

driving control strategyMIND, 268, 272Minimax search in game trees, 84-87, 88,

00, 01, 04, 08Model, semantic, in FOL, 205Modularity of a knowledge representation,

140, 157, 170, 178, 103, 108, 336, 343Modus ponens, 162Mood system, of a grammar, 240Morphemics

in speech understanding, 332-333in transformational grammar, 246

Multiple sources of knowledge. SeeKnowledge source.

Mutilated chessboard problem, 27MYCIN, 151, 157, 105-100

Subject Index402

Named plan, in PAM, 313Natural deduction, in logic, 163-164, 160,

175Natural language features, problematic

agreement, 263ambiguity, 208-211anaphoric reference, 203, 358case ambiguity, 201ellipsis, 320, 358embedding, 263habitability, 328speech acts, 280

Natural language understanding, 3, 8,225-321, 358-350. See also Speechunderstanding.

competence vs. performance in, 245early research, 227-220, 237, 257, 260,

281-287and semantic primitives, 140, 207-214

Natural language understanding, appli-cations

information retrieval, 22, 145, 282, 283,292, 316, 318

machine translation, 207-213, 225, 226,233-238, 273, 274, 279, 281, 288-291

paraphrasing, 140, 211, 255, 274,302-304, 321

question answering, 168-160, 173,185-186, 281, 205, 302

story understanding, 221, 231, 300, 306Negmax formalism for game-tree search,

86-87, 80Network representation. See also Seman-

tic network knowledge representa-tion.

ATN, 186, 230, 233, 261, 263-267, 268,271, 277-270, 202-204, 303, 304, 316

discrimination, 158, 278, 304Finite-state transition diagram, 263-264partitioning, 186pronunciation graphs, 330RTN, 264-266segmented lattice, 330, 337, 353, 356in speech systems, 330, 337spelling graph, 330, 337, 346transition tree, 316-317

Nodecritical, 01depth of, 40expansion of, 46, 55intermediate, 30, 56, 57solvable, 40successor, 26, 33, 46

terminal, 38, 43tip, 80, 87unsolvable, 40, 55

_____Noise, in speech signal, 343Nondeterminism. See Parsing.Nonterminal symbols of a grammar, 230NP-complete problems, 68, 60NUDGE, 221

Obligatory transformation, in agrammar, 247

Observation of a semantic model, 205Operator schemata, 33Operators, in problem solving, 22, 32, 36,

74, 110, 113, 110, 123, 128, 135Optimal solution, in search, 28, 62, 74Optimality, of search algorithm, 65-67,

80, 83Optional transformation, in a grammar,

247Ordered depth-first search, 60, 102Ordered search, 50-62, 64, 72, 77-81, 82,

124Organization of knowledge, 336

PAM, 300, 306, 313-314Parallel processing, 258, 265, 208

Co-routining, 271and direct knowledge representation,

204distributed, 336

Paraphrasing, 140, 211, 255, 274, 302-304,321

Paraplate, in preference semantics, 270,201

PARRY, 257PARSIFAL, 230Parsing, 225, 220, 230-240, 256-272. See

also Grammar; Natural languageunderstanding,

ad hoc, 287with an ATN, 263-267, 203, 349, 355with charts, 260, 268-271, 354control strategies, 230, 258-250derivation tree, 220, 242, 246, 256, 266,

273, 281, 203, 206, 302with extended grammars, 260in LIFER, 316-318by MARGIE'S conceptual analyzer,

302-303nondeterminism, 265grammarless parsers, 260, 261

Subject Index 403

by SHRDLU's PROGRAMMAR,297-298

in speech understanding, 327, 359template matching, 260with a transformational grammar, 260

Partial development, in search, 59, 114Partial expansion. See Partial develop-

ment.Partial functions, operators viewed as, 33Partitioned semantic network, 186, 360Pattern matching, 123, 256, 260, 283-287.

See also Matching.Perceptual primitives, in WHISPER, 204Performance evaluation, of speech sys-

tems, 329Performance grammar, 261, 335, 349, 355,

359. See also Semantic grammar.PHLIQAI, 232Phonemics

in speech understanding, 327, 332-333in transformational grammar, 246

Phonetics, 327, 332-333, 343Phonological component of a transfor-

mational grammar, 248Phrase marker, in a transformational

grammar, 246, 273Phrase-structure grammar, 240-246

compared with transformation grammar,245

definition of, 243in parsing, 260, 262

Planin problem solving, 107, 128, 131, 137in story understanding, 306, 309-310

PLANNER, 151, 155, 171, 175-178,295-207

Planning, 22, 28, 160. See also Problemsolving; Reasoning,

constraint-structured, 203hierarchical, in ABSTRIPS, 135generalized, in STRIPS, 131-134

Plausible-move generation, in game-treesearch, 104

Plausible reasoning, 177Ply, in game trees, 00POPLER, 176Potential solution, in heuristic search,

77-70, 80, 82Pragmatics, in discourse, 240, 327, 332,

334, 350Preconditions, of an operator

in ABSTRIPS, 136in STRIPS, 128, 131, 135

Predicate calculus, 128, 163, 200, 202,207, 290. See also Logic.

Predicate, in logic, 163, 182Preference semantics, 208, 270, 288-201Primitive problem, 36, 38, 74, 121Primitives

perceptual, in WHISPER, 204semantic, 148-149, 183, 108, 207-215,

231, 237, 278, 288-201, 300-303, 306Problem reduction, 7, 114, 110, 201Problem-reduction representation, 25,

36-42, 54, 74, 113Problem representation, 8, 22-28, 32-45

game tree, 25, 43-45, 84AND/OR graph, 26, 38-40, 43, 74,

113, 110, 124problem-reduction, 25, 36-42, 54, 74,

113state space, 26, 33, 105theorem-proving, 25

Problem solving, 7, 21, 58, 74, 100, 113,110, 123, 128, 135, 153, 284, 206.See also Planning; Problem represen-tation; Reasoning; Theorem proving,

generate-and-test, 30human, 285interdependent subproblems, 56, 81-83means-ends analysis, 24, 50, 113, 117,

126, 120, 135, 160operators, 22, 32, 36, 74, 110, 113, 110,

123, 128, 135optimal solution, 28, 62, 74primitive problem, 36, 38, 74, 121problem reduction, 7, 114, 110, 201for robots, 22, 128-130solution, 33state-space search, 30, 35, 46-53, 55,

58-73, 77, 80, 111, 153, 105Problem space. See State space.Procedural attachment, 156, 158, 170,

218-221Procedural-declarative controversy, 151,

230Procedural knowledge, 103, 108, 210Procedural knowledge representation, 146,

149-150, 155-156, 172-179, 219-220,230, 289, 295-297

Procedural semantics, 229-230Process control. See Control strategy.Production rule, 157, 190, 239, 303Production system, 157, 190-100

adaptive, 105conflict resolution in, 102, 107

Subject Index404

Production system (continued)context, 100, 107interpreter, 100-102manageability of, 103, 108

PROGRAMMAR, 207, 310Programming languages for AI. See AI

programming languages.Pronunciation graph, 330Property inheritance. See Inheritance.Propositional calculus, 100, 116, 118,

160-163. See also Logic.Propositional (Fregean) knowledge

representation, 200Prosodies, in speech understanding, 327,

332-334, 350PROSPECTOR, 157, 181, 106, 108PROTOSYNTHEX, 228Pruning, 50, 60, 121, 120, 201. See also

Game-tree search.Pseudo-language, 233Psychology, 157, 180, 103, 201.

human problem solving, 6-7, 14, 285memory, 180, 187, 201, 230

Puzzles. See also Games.blocks world, 2768-puzzle, 32, 51, 62, 67, 6815-puzzle, 68, 73mutilated chessboard, 27Tower of Hanoi, 36-38, 42, 160, 165traveling-salesman problem, 21, 34, 48,

62, 60, 70-71

QA3, 120, 168-160QA4, 176QLISP, 176Quantification, 151, 164, 360Query language, 202Question answering, 168-160, 173,

185-186, 281, 205, 302Quiescence, in game-tree search, 00-100,

103

Random game tree, 02Random text generation, 233, 273Reasoning, 8, 146. See also Control

strategy; Planning; Problem solving,analogical, 146backward, 23-25, 36, 51, 56, 74, 110,

111bottom-up, 24data- or event-driven, 23-24, 108, 220deductive, 146, 205default, 176-177

direction of, 23-24, 108directedness of, 151, 174-177, 185, 188,

103, 210expectation- or goal-driven, 23-24, 183,

107, 216-218, 232, 326, 334, 336, 344extended inference in, 176formal, 146forward, 23-25, 51, 56, 74, 108from a diagram, 201inexact, 195inference in, 146, 188, 213, 228, 231,

236-237, 255, 276, 303-304plausible, 177spreading activation, 185, 187, 180top-down, 24top-down vs. bottom up. See Control

strategy, direction of.Recursive pattern matcher, 256Recursive transition networks (RTN),

264-266Refutation move, in game playing, 102Regular grammar, 243, 245, 263. See also

Finite-state grammar.Representation of knowledge. See Knowl-

edge representation.Resolution method, in logic, 168, 175Response frame, of a knowledge source,

345, 347Rewrite rules, 230, 261, 316. See also

Grammar; Production rule.ROBOT, 232Robot problem solving, 22, 128-130Robotics, 10Rule

of inference, 146, 154-155, 160,162-165, 168, 175

production, 157, 100, 230, 303rewrite, 230, 261, 316

Rule base, of a production system, 100Rule-based system. See Production

system.

SAD-SAM, 158, 227, 237, 260,281-282

SAINT, 123-127SAM, 211, 216, 220, 231, 300, 306,

311-313, 334Scheduler, 347, 356Schema. See Frame knowledge repre-

sentation.SCHOLAR, 186Scientific applications of AI, 221Scope of a knowledge representation, 147

Subject Index 405

Scoring. See Hypothesis scoring.Script knowledge representation, 216-222,

231, 300, 306, 307-300, 311, 334SDC speech system, 337Search, 6, 7, 21, 25, 330, 337, 338, 330,

343, 344Search algorithms. See also Game-tree

search.AND/OR graph search, 54-57, 74-83A* algorithm, 64-73, 80alpha-beta pruning, 88-03, 04, 101bandwidth search, 60, 60-71beam, 337, 341, 350, 356best-first, 50, 60, 102, 360bidirectional, 24, 51-53, 72-73, 74blind, 21, 20-30, 46-57, 58, 61-62, 72,

111breadth-first, 47-48, 56-57, 61, 68, 73,

111depth-first, 40-51, 57, 60, 61, 101, 113,

138, 203fixed ordering, 00, 101full-width, 103generate-and-test, 30heuristic, 21, 28, 20-30, 46, 58-83, 117,

110, 350Heuristic Path Algorithm, 67hierarchical, 135iterative deepening, 100-101length-first, 138minimax, 84-87, 88, 00, 01, 04, 08negmax, 86-87, 80optimality, 65, 66, 67, 80, 83ordered, 50-62, 64, 72, 77-81, 82, 124ordered depth-first, 60, 102in speech systems, 330-340uniform-cost, 48-40, 51, 61, 65, 73

Search graph, 26Search space, 26-28, 58, 04, 330, 343Secondary search, in game trees, 100Segmented lattice, 330, 337, 353, 356Semantic analysis, in natural language

understanding, 228, 230Semantic component, of a transforma-

tional grammar, 248Semantic density, in preference semantics,

200Semantic grammar, 220, 261, 318, 320,

335, 355, 350. See also Performancegrammar.

Semantic interpretation function, inknowledge representation, 200

Semantic marker, 207

Semantic model, in FOL, 205Semantic network knowledge

representation, 156, 172, 180-180,103, 107, 208, 218, 220, 230, 254,276, 277, 303, 330, 355, 360

active structural network, 185fragment matching in, 187partitioning of, 186, 360spreading activation in, 185, 187, 180

Semantic primitives, 148, 140, 183, 108,207-215, 231, 237, 254, 278, 288, 300,306

Semantics, 184, 186, 180, 225, 235, 287,316, 326, 327, 332, 334, 344

generative, 248interpretive, 248preference, 208procedural, 220, 230

Sentential connectives, in logic, 161Short-term memory buffer, in production

systems. See Context.Shortfall density strategy, for hypothesis

scoring in HWIM, 341, 356SHRDLU, 151, 176, 106, 230, 251, 257,

260, 276, 205-200, 310Simulation structure, in FOL, 205SIN, 125-127SIR, 158, 173, 185, 228, 237, 260,

283-284SLIP, 286Slot, of a frame, 158, 216SNIFFER, 188SOLDIER, 125Solution graph, 40, 55Solution, in problem solving, 33Solution tree, 40, 75, 77-70Solvable node, 40SOPHIE, 257, 261Sort, in logic, 163, 166Space planning task, 202Speech acts, 280Speech recognition, 325, 326, 333, 340Speech signal, 332

acoustics, 343allophone, 333, 337, 340intonation, 333noise, 343stress, 333syllable, 333, 343

Speech understanding, 158, 186, 226, 231,257, 250, 267, 202, 325-361

connected speech, 326evaluation of system performance, 320

Subject Index406

Speech understanding (continued)isolated-word recognition, 325, 333, 349morphemics, 332-333network representations in, 330, 337phonemics, 327, 332-333prosodies, 327, 332-334, 359vs. speech recognition, 326

SPEECHLIS, 328, 353Spelling correction, 320Spelling graph, 330, 337, 346Spreading activation, in semantic

networks, 185, 187, 189SRI speech system, 339, 358-361Start symbol, of a grammar, 240State, 22, 32State space, 26, 33, 195

graph, 25, 33-34, 43, 46, 61, 64, 74representation, 24, 32-35, 36, 40-42,

46, 74, 113, 129search, 30, 35, 46-53, 55, 58-73, 77,

80, 111, 153, 195Static evaluation function, in game-tree

search, 87, 96-97, 100Stereotypes, in preference semantics, 289Stimulus frame, of a knowledge source,

345Story grammar, 306Story understanding, 231, 300, 306Stress, in speech understanding, 333STRIPS, 22, 28, 42, 82, 128-134, 135,

138-139, 169STUDENT, 196, 227, 237, 260, 284-285Stylistics, in text generation, 279Subgoals, conjunctive, 111, 119Subproblems, interdependent, 56, 81-83.

See also Problem solving; Subgoals.Successor node, 26, 33, 46Sum cost. See Cost, in search algo-

rithms.Surface structure of a natural language,

247, 252, 273, 274, 277. See alsoSyntax.

Syllable, in speech understanding, 333,343

Symbolic integration, 21, 22, 24, 118,123-127

Syntactic analysis, in natural languageunderstanding, 230

Syntactic categories, of a grammar, 239Syntactic component, of a transforma-

tional grammar, 247Syntactic symmetry, in the Geometry

Theorem Prover, 120

Syntax, 155, 225, 326, 327, 332, 334, 344,346

Systemic grammar, 229, 249-251, 297Systems architecture, for speech under-

standing, 332-342, 353

Table of Connections, in GPS, 115Tapered forward pruning, 104Tautology, in logic, 162Taxonomy, 181. See also Inheritance.Teachable Language Comprehender

(TLC), 185, 228TEIRESIAS, 145, 105-100Template

bare, 288, 290in case grammars, 253matching, in parsing, 260in preference semantics, 270, 288-201in speech recognition, 333, 337, 340,

349word, 349

Terminal node, of an AND/OR graph,38, 43

Terminal symbol, in a grammar, 230Text-based NL systems, 228Text generation, 273-280

in MARGIE, 304random, 233, 273and machine translation, 273-274, 270,

289, 291Textual function, of language, 249Theme, in story understanding, 306,

310-311, 313Theorem proving, 22, 23, 26, 62, 74, 100,

116, 118, 110, 120, 151, 155, 168,171, 175, 188, 207

Theorem-proving representation, 25THNOT, in PLANNER, 176Tic-tac-toe, 43, 04Tip node, of an AND/OR graph, 80, 87Top-down processing, 250, 326, 334, 338,

344, 355, 358, 350. See also Back-ward reasoning; Control strategy;Expectation-driven processing.

Top-down reasoning, 24Top-down vs. bottom-up reasoning, 108TORUS, 186Totally dependent game tree, 02Tower of Hanoi puzzle, 36-38, 42, 160,

165Transfer of expertise, 100Transformational grammar, 220, 237,

245-248, 240, 251, 252

407Subject Index

parsers, 260Transformations, obligatory and optional,

246-247Transition operator. See Legal-move

generator.Transition-tree grammar, in LIFER,

316-317Transitivity system, of a grammar, 240Travel budget manager task, 353Traveling-salesman problem, 21, 34, 48,

62, 60, 70-71Tree. See Grammar; Parsing; Problem

representation.Triangle table, in STRIPS, 131-132Trigger. See Procedural attachment.Truth table, in logic, 162Truth values, in logic, 161Turing machine, 4, 241, 266

Understandability, of knowledgerepres entations, 150, 156-157, 174,193

Uniform-cost search, 48-49, 51, 61, 65, 73Uniform game tree, 91-93Uniform scoring policy, of hypotheses in

HWIM, 340UNITS, 221Universal specialization, in logic, 164Unsolvable node, of an AND/OR graph,

40, 55

Variable domain array, in theGeneral Space Planner, 202

Variable, in logic, 164Verb sense, 278Vision, 10, 330, 334Voice chess, 328, 334, 344

Well-formed formula, in logic, 164WHISPER, 203Word island, in HWIM, 353Word template, 349World knowledge, 226, 230. See also

Domain-specific knowledge; Heuristic.World model, 22, 128, 135

"

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15 Jun 1981 11:21 OUTLIN.TEX[I,DGK] Page 1-4

3. ACT4. MEMOD

F . Bel ief systems

{\bf XII. Automatic Deduction}

A. OverviewB. Resolution-based theorem provingC. Nonresol ution theorem provingD. Applications of theorem provingE. Nonmonotonic logic

{\bf XIII. Vision}

A. OverviewB. Blocks-world understandingC. Processing of visual dataD. Shape understandingE. Representation and control methods in visionF. Sample applications in vision research

{\bf XIV. Robotics}

A. OverviewB. Computation in a physical environmentC. Engineering and kinematicsD. Languages and simulationE. Planning and representation

{\bf XV. Learning and Inductive Inference}

A. OverviewB. Rote learningC. Advice takingD. Learning from examples

1. Overview2. Adaptive learning3. Learning single concepts4. Learning multiple concepts5. Learning by doing

{\bf XVI. Planning and Problem Solving}

A. OverviewB. Linear plannersC. Hierarchical planners

1. NOAH and extensions2. MOLGEN

D. Opportunistic planning\par}

\bye