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A New Frontier in Computation— Computation with Information Described in Natural Language Lotfi A. Zadeh Computer Science Division Department of EECS UC Berkeley ISAI Beijing, China August 1, 2006 URL: http://www-bisc.cs.berkeley.edu URL: http://www.cs.berkeley.edu/~zadeh/ Email: [email protected] PREAMBLE What is meant by Computation with Information Described in Natural Language, or NL-Computation, for short? Does NL-Computation constitute a new frontier in computation? Do existing bivalent-logic-based approaches to natural language processing provide a basis for NLComputation? What are the basic concepts and ideas which underlie NL-Computation? These are some of the issues which are addressed in the following. 2 /168 LAZ 7/28/2006 A HISTORICAL NOTE 3 /168 NL-Computation is a culmination of my longstanding interest in exploring what I have always believed to be a central issue in fuzzy logic, namely, the relationship between fuzzy logic and natural languages. My principal papers on this theme are the following. LAZ 7/28/2006 TIMELINE 1971 Quantitave Fuzzy Semantics 1973, 1975 Lynguistic Variables and Fuzzy-if-then rules 1978 Theory of Approximate Reasoning 1978 PRUF-a meaning representation language for natural languages 1979 Fuzzy Sets and Information Granularity 1982 Test-score semantics for natural languages and meaning representation via PRUF 1986 Generalized Constraint 1996 Fuzzy Logic=Computing with Words 1999 From computing with numbers to computing with words --from manipulation of measurements to manipulation of perceptions 2005 Generalized Theory of Uncertainty (GTU) 4 /168 LAZ 7/28/2006 BASIC STRUCTURE OF NL-COMPUTATION Basically, NL-Computation is a system of computation in which the objects of computation are words and propositions drawn from a natural language COMPUTATION PRECISIATION NL p q information question Pre1(p) Pren(p) Pre1(q) Pren(q) bridge from NL to MATH (generalized-constraint-based) 5 /168 reduction solution ans(q/p) reduction to final solution a standard problem (generalized-constraint-based) LAZ 7/28/2006 KEY IDEAS IN NL-COMPUTATION FUNDAMENTAL THESIS Information = generalized constraint proposition is a carrier of information MEANING POSTULATE proposition = generalized constraint 6 /168 In our approach, NL-Computation is reduced to computation with generalized constraints, that is, to generalized-constraint-based computation. NL-Computation is based on fuzzy logic. NL-Computation is closely related to Computing with Words (CW) LAZ 7/28/2006 FUZZY LOGIC—KEY POINTS “Fuzzy logic” is not fuzzy logic Fuzzy logic is a precise logic of imprecision The principal distinguishing features of fuzzy logic are: a) In fuzzy logic everything is, or is allowed to be graduated, that is, be a matter of degree or, equivalently fuzzy b) In fuzzy logic everything is allowed to be granulated 7 /168 LAZ 7/28/2006 ANALOGY In bivalent logic, one writes with a ballpoint pen In fuzzy logic, one writes with a spray pen which has a precisely defined spray pattern This simple analogy suggests many mathematical problems Y X 8 /168 What is the maximum value of f? Precisiation/imprecisiation principle LAZ 7/28/2006 EXAMPLE OF NL-COMPUTATION Trip planning I am planning to drive from Berkeley to Santa Barbara, with stopover for lunch in Monterey. Usually, it takes about two hours to get to Monterey. Usually it takes about one hour to have lunch. It is likely that it will take about six hours to get from Monterey to Santa Barbara. At what time should I leave Berkeley to get to Santa Barbara, with high probability, before about 6 pm? 9 /168 LAZ 7/28/2006 LOOKAHEAD in NL-Computation, computations are for the most part protoformal, that is, the objects of computation are protoforms (deep structures). example C1 C3 C5 C2 C4 C5=C1+C2+C3+C4 what we have is partial (granular) information about the Ci which is expressed as a generalized constraint i(Ci)=GC(Ci) example: usually (C2 is about 2 hours) 10 /168 LAZ 7/28/2006 A BASIC CONCEPT IN NL-COMPUTATION: PROTOFORM EQUIVALENCE protoform = abstracted summary surface structure deep structure most Swedes are tall most balls are large Count (G[A is B]/G[A]) is Q protoform 11 /168 LAZ 7/28/2006 A BASIC CONCEPT IN NL-COMPUTATION: INFORMATION GRANULARITY A granular value of X singular value of X universe of discourse singular: X is a singleton granular: X isr A granule a granule is defined by a generalized constraint example: X: unemployment a: 7.3% A: high 12 /168 LAZ 7/28/2006 ATTRIBUTES OF A GRANULE Probability measure Possibility measure Verity measure Length Volume Entropy 13 /168 LAZ 7/28/2006 PRECISIATION 1 X: time of departure U: travel time from Berkeley to Monterey V: duration of lunch W: travel time from Monterey to Santa Barbara X is a fuzzy variable; U, V, and W are imprecisely described fuzzy random variables *a: approximately a Prob(((?X + U + V + W) *18)) is high 14 /168 LAZ 7/28/2006 SIMPLIFIED PROBLEM—LOOKAHEAD Problem ? Z=*a + usually(*b) X Y : granular values precisiation granular computing 15 /168 LAZ 7/28/2006 PRECISIATION OF “approximately a,” *a 1 singleton s-precisiation 0 a cg-precisiation x 1 interval 0 p a x probability distribution g-precisiation 0 a x possibility distribution 0 a x 1 0 16 /168 fuzzy graph 20 25 x LAZ 7/28/2006 CONTINUED p bimodal distribution g-precisiation 0 17 /168 x LAZ 7/28/2006 CONTINUED A A *a is A u B B *b is B u usually usually is C usually (*b) B ( v ) p( v )dv 18 /168 0 p(v) 1 u is usually LAZ 7/28/2006 CONTINUED ( p ) usually ( B ( v ) p( v )dv ) p * x ( v ) p( v u ) p(v) p*(v)=p(v-u) v Z ( p * ( w )) supp ,v ( p( v )) A ( u ) subject to: 19 /168 w v u LAZ 7/28/2006 EXTENSION PRINCIPLE (Zadeh 1965, 1975) Y=f(X) singular values granulation Y*=f*(X*) granular values example f(X) is A g(X) is B B=supu(A(f(u)) subject to v=g(u) 20 /168 LAZ 7/28/2006 MAMDANI Y=f(X) granular f f*: if X is Ai then Y is Bi, f* is Ii AiBi X is a Y is iAi(a)Bi 21 /168 i=1, …, n LAZ 7/28/2006 EXAMPLES OF NL-COMPUTATION Balls-in-box A box contains about twenty balls of various sizes. Most are large. What is the number of small balls? What is the probability that a ball drawn at random is neither small nor large? Temperature Usually the temperature is not very low and not very high. What is the average temperature? Tall Swedes Most Swedes are tall. How many are short? What is the average height of Swedes? Flight delay Usually most United Airlines flights from San Francisco leave on time. What is the probability that my flight will be delayed? 22 /168 LAZ 7/28/2006 CONTINUED Maximization f is a function from reals to reals described as: If X is small then Y is small; if X is medium then Y is large; if X is large then Y is small. What is the maximum of f? Expected value X is a real valued random variable. Usually, X is much larger than approximately a, and much smaller than approximately b, where a and b are real numbers, with a < b. What is the expected value of X? 23 /168 LAZ 7/28/2006 BASIC POINTS 24 /168 Much of human knowledge is expressed in natural language A natural language is basically a system for describing perceptions Perceptions are intrinsically imprecise, reflecting the bounded ability of sensory organs, and ultimately the brain, to resolve detail and store information Imprecision of perceptions is passed on to natural languages, resulting in semantic imprecision Semantic imprecision of natural languages stands in the way of application of machinery of natural languages processing to computation with information described in natural language LAZ 7/28/2006 NL-CAPABILITY NL-capability = capability to compute with information described in natural language Existing scientific theories do not have NL-capability In particular, probability theory does not have NL-capability 25 /168 LAZ 7/28/2006 26 /168 LAZ 7/28/2006 UNDERSTANDING VS. PRECISIATION Understanding precedes precisiation I understand what you said, but can you be more precise Beyond reasonable doubt Use with adequate ventilation precisiation Unemployment is high unemployment is over 5% Where do you draw the line? Paraphrase: The US Constitution is an invitation to argue over where to draw the line Where to draw the line is a key issue in legal arguments 27 /168 LAZ 7/28/2006 THE CONCEPT OF -PRECISION / PRECISIATION 28 /168 In NL-Computation, precision is a concept with many facets. This perception of precisition leads to the concept of precision/precisiation, where is an indexical variable whose values are labels of facets of precision = v (value) v-precise, v-precisiation v-imprecise, v-imprecisiation = m (meaning) m-precise, m-precisiation m-imprecise, m-imprecisiation = mh + mm + s + g + gc +bl + fl + … LAZ 7/28/2006 WHAT IS PRECISE? PRECISE v-precise precise value m-precise precise meaning • p: X is a Gaussian random variable with mean m and variance 2. m and 2 are precisely defined real numbers • p is v-imprecise and m-precise • p: X is in the interval [a, b]. a and b are precisely defined real numbers • p is v-imprecise and m-precise m-precise = mathematically well-defined 29 /168 LAZ 7/28/2006 PRECISIATION AND IMPRECISIATION v-imprecisiation 1 0 a x v-precisiation m-precise 1 0 a x m-precise v-imprecise v-precise 1 v-imprecisiation 0 30 /168 x If X is small then Y is small If X is medium then Y is large If X is large then Y is small v-precise v-imprecise m-precise m-imprecise LAZ 7/28/2006 IMPRECISIATION/ SUMMARIZATION OF FUNCTIONS L v-imprecisiation M S summarization If X is small then Y is small If X is medium then Y is large If X is large then Y is small 0 S M L If X is small then Y is small mm-precisiation If X is medium then Y is large If X is large then Y is small (X, Y) is small small + medium large + large small fuzzy graph 31 /168 LAZ 7/28/2006 SUMMARIZATION OF T-NORMS S M L 32 /168 S M L S S S S M M S M L To facilitate the chore of an appropriate t-norm, each t-norm should be associated with a summary LAZ 7/28/2006 APPROXIMATION VS. SUMMARIZATION y 0 summarization may be viewed as a form of imprecisiation y approximation 0 x x granule L y 0 M summarization S x 0 S 33 /168 M L LAZ 7/28/2006 V-PRECISIATION X: variable g-precisiation A X s-precisiation s-precisiation unemployment 7.3% high g-precisiation • s-precisiation is used routinely in scientific theories and especially in probability theory • defuzzification may be viewed as an instance of sprecisiation 34 /168 LAZ 7/28/2006 PRECISIATION/IMPRECISIATION PRINCIPLE (Zadeh 2005) a*: approximately a simple version f(*a)= *f(a) Y Y X 35 /168 X LAZ 7/28/2006 PRECISE SOLUTION level set undominated 36 /168 LAZ 7/28/2006 THE CONCEPTS OF PRECISIEND AND PRECISIAND precisiend precisiand object of precisiation variable value of X lexeme precisiation result of precisiation X v-precisiation X v-precisiand ℓ concept Pre (ℓ) proposition m-precisiation question command 37 /168 m-precisiand model of meaning LAZ 7/28/2006 MODALITIES OF m-PRECISIATION m-precisiation mh-precisiation human-oriented ℓ 38 /168 m-precisiation mm-precisiation machine-oriented precisiand of ℓ (Pre(ℓ)) LAZ 7/28/2006 PRECISIATION AND DISAMBIGUATION Examples: • Overeating causes obesity most of those who overeat become obese Count(become.obese/overeat) is most • Obesity is caused by overeating are obese were overeating Count(were.overeating/obese) is most 39 /168 most of those who LAZ 7/28/2006 PRECISIATION/ DISAMBIGUATION P: most tall Swedes P(A) is? POPULATION (Swedes) tall Swedes A P mh-precisiation P1 P2 40 /168 mm-precisiation mm-precisiation P1: most of tall Swedes P2: mostly tall Swedes Count(A/tall.Swedes) is most Count(tall.Swedes/A) is most LAZ 7/28/2006 BASIC STRUCTURE OF DEFINITIONS definiens definiendum (idea/perception) concept mh-precisiation mh-precisiand mm-precisiation mm-precisiand cointension cointension cointension= wellness of fit of meaning mh-precisiation bear market 41 /168 mm-precisiation Declining market with expectation of further decline We classify a bear market as a 30 percent decline after 50 days, or a 13 percent decline after 145 days. (Robert Shuster) LAZ 7/28/2006 EXAMPLES: MOUNTAIN, CLUSTER, STABILITY mh-precisiation mountain mm-precisiation 42 /168 A natural raised part of the earth’s surface, usually rising more or less abruptly, and larger than a hill ? LAZ 7/28/2006 CONTINUED mh-precisiation cluster mm-precisiation A number of things of the same sort gathered together or growing together; bunch ? • the concepts of mountain and cluster are PFequivalent, that is, have the same deep structure mh-precisiation stability mm-precisiation mm-precisiation 43 /168 The capacity of an object to return to equilibrium after having been displaced Lyapuonov definition fuzzy stability definition LAZ 7/28/2006 RATIONALE FOR IMPRECISIATION IMPRECISIATION PRINCIPLE p: X is V value of X variable X: real-valued variable X: (X1, …, Xn) X: function X: relation … V is v-precise if V is a singleton (singular) v-imprecisiation: singular granular 44 /168 LAZ 7/28/2006 v-IMPRECISIATION v-imprecisiation forced deliberate forced: V is not known precisely deliberate: V need not be known precisely v-imprecisiation principle: Precision carries a cost. If there is a tolerance for imprecision, exploit it by employing v-imprecisiation to achieve lower cost, robustness, tractability, decision-relevance and higher level of confidence 45 /168 LAZ 7/28/2006 EXAMPLE: V-IMPRECISIATION v-precise v-imprecise 1 deliberate 0 x If X is small then Y is small If X is medium then Y is large If X is large then Y is small perception forced 46 /168 LAZ 7/28/2006 GRANULATION REVISITED Granulation is a derivative of v-imprecisiation principle continuous Age quantized 1, 2, 3, 4, 5, … granulated young + middle-aged + old µ µ 1 1 0 quantized Age 0 middle young -aged old Age granulated granulation = v-imprecisiation / m-precisiation 47 /168 LAZ 7/28/2006 KEY POINT • 48 /168 Granulation plays a key role in human cognition In human cognition, v-imprecisiation is followed by mh-precisiation. Granulation is mh-precisiation-based In fuzzy logic, v-imprecisiation is followed by mm-precisiation. Granulation is mmprecisiation-based mm-precisiation-based granulation is a major contribution of fuzzy logic. No other logical system offers this capability LAZ 7/28/2006 DIGRESSION—EXTENSION VS. INTENSION extension and intension are concepts drawn from logic and linguistics basic idea name attribute attribute name value object attribute attribute name value object =(name; (attribute1, value1), …, (attribute n, value n)) more compactly object = (name, (attribute, value)) n-ary n-ary 49 /168 LAZ 7/28/2006 OPERATIONS ON OBJECTS function name-based extensional definition object attribute-based intensional definition (algorithmic) object: (Michael, (gender, male), …, (age, 25)) son (Michael) = Ron 50 /168 LAZ 7/28/2006 PREDICATE (PROPERTY, CONCEPT, SET, MEMBERSHIP FUNCTION, INPUT-OUTPUT RELATION) A predicate, P, is a truth-valued function U: universe of discourse generic object X P 51 /168 D(P) Denotation of P: D(P)= {X|P(X)} Extension of P: Ext(P)= D(P) if P(X) is name-based Intension of P: Int(P)= D(P) if P(X) is attribute-based P(X): open predicate (X is a free variable) P(a): closed predicate (X is a bound variable(P is grounded)) LAZ 7/28/2006 EXAMPLE U: population X P: bachelor D(bachelor) Ext (bachelor)= {X|bachelor (X)} gender( X ) man { X | Int(bachelor)= marital.status( X ) sin gle } 52 /168 LAZ 7/28/2006 PRINCIPAL MODES OF DEFINITION Extension: name-based meaning Intension: attribute-based meaning Extensional: P={u1, …, un} e-meaning of P Ostensive: P={u, uk, ul} o-meaning of P exemplars 53 /168 Intensional: P={u|P(u)}, i-meaning of P LAZ 7/28/2006 PROPOSITION (TENTATIVE) A proposition, p, is a sentence which may be expressed as P(object). Equivalently, p, is a closed predicate. Equivalently, p = object is P young(Valentina), e-meaning very simple example: extensional p: Valentina is young young(Age(Valentina), i-meaning example intensional p: most Swedes are tall P: most object: Count(tall.Swedes/Swedes) p most(Count(tall.Swedes/Swedes)) i-meaning of p is associated with i-meaning of P and imeaning of object Question: D(most.tall.Swedes)? 54 /168 LAZ 7/28/2006 THE CONCEPT OF COINTENSION 55 /168 p, q are predicates or propositions CI(p,q): cointension of p and q: degree of match between the i-meanings of p and q q is cointensive w/n to p if GI(p, q) is high A definition is cointensive if CI(definiendum, definiens) is high In practice, CI(p,q) is frequently associated with o-meaning of p and i-meaning of q The o-meaning of the definiendum is perception-based LAZ 7/28/2006 THE CONCEPTS OF COINTENSION AND RESTRICTIVE COINTENSION U: universe of discourse q D(q) p D(p) restriction R 56 /168 CI(p,q)=degree of proximity of D(p) and D(q) Cointension of q relative to p=degree of subsethood of D(q) in D(p) Restricted cointension: U is restricted to R LAZ 7/28/2006 THE CONCEPT OF COINTENSIVE PRECISIATION Precisiation of a concept or proposition, p, is cointensive if Pre(p) is cointensive with p. Example: bear market We classify a bear market as a 30 percent decline after 50 days, or a 13 percent decline after 145 days. (Robert Shuster) This definition is clearly not cointensive 57 /168 LAZ 7/28/2006 KEY POINTS Precisiand=model of meaning In general, p, may be precisiated in many different ways, resulting in precisiands Pre1(p), …, Pren(p), each of which is associated with the degree, CIi, of cointension of Prei(p), i= 1, …, n. In general, CIi is context-dependent. p precisiation1 Pre1(p) precisiation2 Pre2(p) precisiationn Pren(p) : C1 : C2 : Cn Precisiation is necessary but not sufficient To serve its pupose, precisiation must be cointensive Cointensive precisiation is a key to mechanization of natural language understanding 58 /168 LAZ 7/28/2006 AN IMPORTANT IMPLICATION FOR SCIENCE 59 /168 It is a deep-seated tradition in science to employ the conceptual structure of bivalent logic and probability theory as a basis for formulation of definitions of concepts. What is widely unrecognized is that, in reality, most concepts are fuzzy rather than bivalent, and that, in general, it is not possible to formulate a cointensive definition of a fuzzy concept within the conceptual structure of bivalent logic and probability theory. LAZ 7/28/2006 EXAMPLES OF FUZZY CONCEPTS WHOSE STANDARD, BIVALENT-LOGIC-BASED DEFINITIONS ARE NOT COINTENSIVE 60 /168 stability causality relevance bear market recession mountain • independence • stationarity • cluster • grammar • risk • linearity LAZ 7/28/2006 ANALOGY S system M(S) modelization ℓ lexeme model Pre(ℓ) precisiation precisiand • input-output relation intension (test-score function) • system analysis semantical analysis (Frege’s Principle of Compositionality) • degree of match between M(S) and S cointension • In general, it is not possible to construct a cointensive model of a nonlinear system from linear components 61 /168 LAZ 7/28/2006 CHOICE OF PRECISIAND Cointension and tractability are contravariant cointension tractability complexity 62 /168 To be tractable, precisiation should not be complex An optimal choice is one which achieves a compromise between tractability and cointension LAZ 7/28/2006 THE KEY IDEA: MEANING POSTULATE In NL-computation, a proposition, p, is precisiated by expressing its meaning as a generalized constraint. In this sense, the concept of a generalized constraint serves as a bridge from natural languages to mathematics. NL Mathematics p precisiation p* (GC(p)) generalized constraint • The concept of a generalized constraint is the centerpiece of NL-computation 63 /168 LAZ 7/28/2006 TEST-SCORE SEMANTICS (ZADEH 1982) Prinicipal Concepts and Ideas 64 /168 Test-score semantics has the same conceptual structure as systems analysis In test-score semantics, a lexeme, p, is viewed as a composite constraint Each constraint is associated with a test-score function which defines the degree to which the constraint is satisfied given the values of constraint variables Semantic analysis involves computation of the testscore function associated with p in terms of the testscore functions associated with f components of p the operation of composition and the resulting testscore function constitute the meaning of p LAZ 7/28/2006 CONTINUED 65 /168 Constraints are represented as relations The system of relations associated with p constitutes an explanatory database; ED ED may be viewed as a description of a possible world Test-score semantics has a much higher expressive power than possible-world semantics LAZ 7/28/2006 EXAMPLE p: young men like young women p* most young men like most young women POPULATION men women Namei Namej ED (explanatory database) possible world young ED= 66 /168 POPULATION [Name; Gender; Age] + LIKES [Name1; Name2; ] + YOUNG [Age; ] + MOST [Proportion; ] LAZ 7/28/2006 CONTINUED P: likes mostly young women women liked by Namei young women Namei P(Namei): Count ((POPULATION [Name; Gender is F; Age is young])/ LIKES [Name is Namei; Name2; Gender is F; Age]) is most ts(p): Count (POPULATION[Name is P]/ POPULATION [Name; Gender is M; Age is young]) is most 67 /168 LAZ 7/28/2006 68 /168 LAZ 7/28/2006 GENERALIZED CONSTRAINT (Zadeh 1986) • Bivalent constraint (hard, inelastic, categorical:) XC constraining bivalent relation Generalized constraint: X isr R constraining non-bivalent (fuzzy) relation index of modality (defines semantics) constrained variable r: | = | | | | … | blank | p | v | u | rs | fg | ps |… bivalent primary open and closed constraints 69 /168 LAZ 7/28/2006 • CONTINUED constrained variable • X is an n-ary variable, X= (X1, …, Xn) • X is a proposition, e.g., Leslie is tall • X is a function of another variable: X=f(Y) • X is conditioned on another variable, X/Y • X has a structure, e.g., X= Location (Residence(Carol)) • X is a generalized constraint, X: Y isr R • X is a group variable. In this case, there is a group, G: (Name1, …, Namen), with each member of the group, Namei, i =1, …, n, associated with an attribute-value, hi, of attribute H. hi may be vector-valued. Symbolically 70 /168 LAZ 7/28/2006 CONTINUED G = (Name1, …, Namen) G[H] = (Name1/h1, …, Namen/hn) G[H is A] = (µA(hi)/Name1, …, µA(hn)/Namen) Basically, G[H] is a relation and G[H is A] is a fuzzy restriction of G[H] Example: tall Swedes 71 /168 Swedes[Height is tall] LAZ 7/28/2006 SIMPLE EXAMPLES “Check-out time is 1 pm,” is an instance of a generalized constraint on check-out time “Speed limit is 100km/h” is an instance of a generalized constraint on speed “Vera is a divorcee with two young children,” is an instance of a generalized constraint on Vera’s age 72 /168 LAZ 7/28/2006 GENERALIZED CONSTRAINT—MODALITY r X isr R r: = r: ≤ r: r: blank equality constraint: X=R is abbreviation of X is=R inequality constraint: X ≤ R subsethood constraint: X R possibilistic constraint; X is R; R is the possibility distribution of X r: v veristic constraint; X isv R; R is the verity distribution of X r: p probabilistic constraint; X isp R; R is the probability distribution of X Standard constraints: bivalent possibilistic, bivalent veristic and probabilistic 73 /168 LAZ 7/28/2006 CONTINUED r: bm bimodal constraint; X is a random variable; R is a bimodal distribution r: rs random set constraint; X isrs R; R is the setvalued probability distribution of X r: fg fuzzy graph constraint; X isfg R; X is a function and R is its fuzzy graph r: u usuality constraint; X isu R means usually (X is R) r: g group constraint; X isg R means that R constrains the attribute-values of the group 74 /168 LAZ 7/28/2006 PRIMARY GENERALIZED CONSTRAINTS Possibilistic: X is R Probabilistic: X isp R Veristic: X isv R Primary constraints are formalizations of three basic perceptions: (a) perception of possibility; (b) perception of likelihood; and (c) perception of truth In this perspective, probability may be viewed as an attribute of perception of likelihood 75 /168 LAZ 7/28/2006 EXAMPLES: POSSIBILISTIC Monika is young Age (Monika) is young X R Monika is much younger than Maria (Age (Monika), Age (Maria)) is much younger X R most Swedes are tall Count (tall.Swedes/Swedes) is most X 76 /168 R LAZ 7/28/2006 EXAMPLES: PROBABILISITIC X is a normally distributed random variable with mean m and variance 2 X isp N(m, 2) X is a random variable taking the values u1, u2, u3 with probabilities p1, p2 and p3, respectively X isp (p1\u1+p2\u2+p3\u3) 77 /168 LAZ 7/28/2006 EXAMPLES: VERISTIC 78 /168 Robert is half German, quarter French and quarter Italian Ethnicity (Robert) isv (0.5|German + 0.25|French + 0.25|Italian) Robert resided in London from 1985 to 1990 Reside (Robert, London) isv [1985, 1990] LAZ 7/28/2006 STANDARD CONSTRAINTS Bivalent possibilistic: X C (crisp set) Bivalent veristic: Ver(p) is true or false Probabilistic: X isp R Standard constraints are instances of generalized constraints which underlie methods based on bivalent logic and probability theory 79 /168 LAZ 7/28/2006 GENERALIZED CONSTRAINT—SEMANTICS A generalized constraint, GC, is associated with a test-score function, ts(u), which associates with each object, u, to which the constraint is applicable, the degree to which u satisfies the constraint. Usually, ts(u) is a point in the unit interval. However, if necessary, it may be an element of a semi-ring, a lattice, or more generally, a partially ordered set, or a bimodal distribution. example: possibilistic constraint, X is R X is R Poss(X=u) = µR(u) ts(u) = µR(u) 80 /168 LAZ 7/28/2006 TEST-SCORE FUNCTION 81 /168 GC(X): generalized constraint on X X takes values in U= {u} test-score function ts(u): degree to which u satisfies GC ts(u) may be defined (a) directly (extensionally) as a function of u; or indirectly (intensionally) as a function of attributes of u intensional definition=attribute-based definition example (a) Andrea is tall 0.9 (b) Andrea’s height is 175cm; µtall(175)=0.9; Andrea is 0.9 tall LAZ 7/28/2006 CONSTRAINT QUALIFICATION p isr R means r-value of p is R in particular p isp R Prob(p) is R (probability qualification) p isv R Tr(p) is R (truth (verity) qualification) p is R Poss(p) is R (possibility qualification) examples (X is small) isp likely Prob{X is small} is likely (X is small) isv very true Ver{X is small} is very true (X isu R) Prob{X is R} is usually 82 /168 LAZ 7/28/2006 GENERALIZED CONSTRAINT LANGUAGE (GCL) GCL is an abstract language GCL is generated by combination, qualification, propagation and counterpropagation of generalized constraints examples of elements of GCL X/Age(Monika) is R/young (annotated element) (X isp R) and (X,Y) is S) (X isr R) is unlikely) and (X iss S) is likely If X is A then Y is B the language of fuzzy if-then rules is a sublanguage of GCL deduction= generalized constraint propagation and counterpropagation the language of fuzzy if-then rules is a sublanguage of GCL LAZ 7/28/2006 83 /168 CONSTRAINTS generalized constraints primary constraints standard constraints generalized: X isr R , r: possibilistic, probabilistic, veristic, random set, usuality, group, … primary: possibilistic, probabilistic, veristic standard: bivalent possibilistic, probabilistic, bivalent veristic existing scientific theories are based on primary constraints 84 /168 LAZ 7/28/2006 PRECISIATION = TRANSLATION INTO GCL BASIC STRUCTURE NL p GCL precisiation translation p* precisiand of p GC(p) generalized constraint annotation p X/A isr R/B GC-form of p example p: Carol lives in a small city near San Francisco X/Location(Residence(Carol)) is R/NEAR[City] SMALL[City] 85 /168 LAZ 7/28/2006 v-PRECISIATION s-precisiation conventional (degranulation) *a precisiation g-precisiation GCL-based (granulation) a approximately a *a p precisiation proposition X isr R GC-form common practice in probability theory • cg-precisiation: crisp granular precisiation 86 /168 LAZ 7/28/2006 PRECISIATION OF “approximately a,” *a 1 singleton s-precisiation 0 a cg-precisiation x 1 interval 0 p a x probability distribution g-precisiation 0 a x possibility distribution 0 a x 1 0 87 /168 fuzzy graph 20 25 x LAZ 7/28/2006 CONTINUED p bimodal distribution g-precisiation 0 x GCL-based (maximal generality) *a g-precisiation X isr R GC-form 88 /168 LAZ 7/28/2006 EXAMPLE • p: Speed limit is 100 km/h poss cg-precisiation r = blank (possibilistic) p 100 110 speed poss g-precisiation r = blank (possibilistic) p 100 110 prob g-precisiation r = p (probabilistic) p 100 89 /168 110 speed LAZ 7/28/2006 CONTINUED prob g-precisiation r = bm (bimodal) p 100 110 120 speed If Speed is less than *110, Prob(Ticket) is low If Speed is between *110 and *120, Prob(Ticket) is medium If Speed is greater than *120, Prob(Ticket) is high 90 /168 LAZ 7/28/2006 THE CONCEPT OF GRANULAR VALUE X is a singular value singleton X is A granular value granule A is defined as a generalized constraint example X is small granular value fuzzy set 91 /168 LAZ 7/28/2006 GRANULAR COMPUTING (GrC) The objects of computation in granular computing are granular values of variables and parameters Granular computing has a position of centrality in fuzzy logic Granular computing plays a key role in precisiation and deduction Informally granular computing=ballpark computing 92 /168 LAZ 7/28/2006 GRANULAR DEFINITION OF A FUNCTION Y f granule L M S 0 0 Y S medium x large f* (fuzzy graph) 0 93 /168 X f M perception summary L f* : if X is small then Y is small if X is medium then Y is large if X is large then Y is small LAZ 7/28/2006 PRECISIATION AND DEDUCTION p: most Swedes are tall p*: Count(tall.Swedes/Swedes) is most further precisiation X(h): height density function (not known) X(h)du: fraction of Swedes whose height is in [h, h+du], a h b 94 /168 b a X ( h )du 1 LAZ 7/28/2006 PRECISIATION AND CALIBRATION µtall(h): membership function of tall (known) µmost(u): membership function of most (known) height most 1 1 0 0 1 height 0.5 1 fraction X(h) height density function 0 95 /168 a b h (height) LAZ 7/28/2006 CONTINUED fraction of tall Swedes: b a X ( h )tall ( h )dh constraint on X(h) b a X ( h )tall ( h )dh is most granular value ( X ) most ( b a X ( h )tall ( h )dh ) 96 /168 LAZ 7/28/2006 DEDUCTION q: How many Swedes are short q*: b a X ( h ) short ( h )dh is ? Q deduction: b a X ( h )tall ( h )dh is most b a X ( h ) short ( h )dh is ? Q given needed • Frege principle of compositionality—precisiated version • precisiation of a proposition requires precisiations (calibrations) of its constituents 97 /168 LAZ 7/28/2006 EXTENSION PRINCIPLE Zadeh 1965, 1975 f(X) is A g(X) is B B ( v ) supu A ( f ( u )) subject to v g( u ) 98 /168 LAZ 7/28/2006 CONTINUED deduction: b a X ( h )tall ( h )dh b a X ( h ) short ( h )dh is ? Q given needed solution: Q ( v ) sup X ( most ( b a X ( h )tall ( h )dh )) subject to v b a X ( h ) short ( h )dh b a 99 /168 X ( h )dh 1 LAZ 7/28/2006 CONTINUED q: What is the average height of Swedes? q*: b a X ( h )hdh is ? Q deduction: is most b a X ( h )tall ( h )dh b a X ( h )hdh is ? Q 100 /168 LAZ 7/28/2006 LOOKAHEAD--PROTOFORMAL DEDUCTION Example: most Swedes are tall 1/nCount(G[H is R]) is Q Height 101 /168 LAZ 7/28/2006 PROTOFORMAL DEDUCTION RULE 1/nCount(G[H is R]) is Q 1/nCount(G[H is S]) is T i µR(hi) is Q i µS(hi) is T µT(v) = suph1, …, hn(µQ(i µR(hi)) subject to v = i µS(hi) values of H: h1, …, hn 102 /168 LAZ 7/28/2006 PROTOFORM LANGUAGE AND PROTOFORMAL DEDUCTION 103 /168 LAZ 7/28/2006 THE CONCEPT OF A PROTOFORM PREAMBLE 104 /168 As we move further into the age of machine intelligence and automated reasoning, a daunting problem becomes harder and harder to master. How can we cope with the explosive growth in knowledge, information and data. How can we locate—and infer from—decision-relevant information which is embedded in a large database. Among the many concepts that relate to this issue there are four that stand out in importance: search, precisiation and deduction. In relation to these concepts, a basic underlying concept is that of a protoform—a concept which is centered on the confluence of abstraction and summarization LAZ 7/28/2006 WHAT IS A PROTOFORM? protoform = abbreviation of prototypical form informally, a protoform, A, of an object, B, written as A=PF(B), is an abstracted summary of B usually, B is lexical entity such as proposition, question, command, scenario, decision problem, etc more generally, B may be a relation, system, geometrical form or an object of arbitrary complexity usually, A is a symbolic expression, but, like B, it may be a complex object the primary function of PF(B) is to place in evidence the deep semantic structure of B 105 /168 LAZ 7/28/2006 CONTINUED object space object summarization protoform space summary of p protoform abstraction p S(p) A(S(p)) PF(p) PF(p): abstracted summary of p deep structure of p • protoform equivalence • protoform similarity 106 /168 LAZ 7/28/2006 PROTOFORMS object space protoform space PF-equivalence class at a given level of abstraction and summarization, objects p and q are PF-equivalent if PF(p)=PF(q) example p: Most Swedes are tall q: Few professors are rich 107 /168 Count (A/B) is Q Count (A/B) is Q LAZ 7/28/2006 EXAMPLES instantiation Monika is young Age(Monika) is young A(B) is C abstraction Monika is much younger than Robert (Age(Monika), Age(Robert) is much.younger D(A(B), A(C)) is E Usually Robert returns from work at about 6:15pm Prob{Time(Return(Robert)} is 6:15*} is usually Prob{A(B) is C} is D usually 6:15* Return(Robert) Time 108 /168 LAZ 7/28/2006 CONTINUED EXTENSION VS INTENSION Q A’s are B’s (attribute-free; extension) most Swedes are tall 1 Count(G[H is A]) is Q n (attribute-based; intension) 109 /168 LAZ 7/28/2006 EXAMPLES Alan has severe back pain. He goes to see a doctor. The doctor tells him that there are two options: (1) do nothing; and (2) do surgery. In the case of surgery, there are two possibilities: (a) surgery is successful, in which case Alan will be pain free; and (b) surgery is not successful, in which case Alan will be paralyzed from the neck down. Question: Should Alan elect surgery? Y gain 0 110 /168 2 option 2 option 1 Y object 0 1 i-protoform X 0 X LAZ 7/28/2006 PROTOFORMAL DEDUCTION NL GCL PFL p precisiation p* summarization q precisiation q* abstraction WKM World Knowledge Module q** DM r** deduction module 111 /168 p** a answer LAZ 7/28/2006 PROTOFORMAL DEDUCTION Rules of deduction in the Deduction Database (DDB) are protoformal examples: (a) compositional rule of inference X is A symbolic B ( v ) sup( A ( u ) B ( u ,v )) (X, Y) is B computational Y is A°B (b) Extension Principle X is A Y = f(X) y ( v ) supu ( A ( u )) Subject to: v f (u ) Y = f(A) 112 /168 symbolic computational LAZ 7/28/2006 RULES OF DEDUCTION Rules of deduction are basically rules governing generalized constraint propagation The principal rule of deduction is the extension principle X is A f(X,) is B symbolic 113 /168 B ( v ) supu ( A ( u ) Subject to: v f (u ) computational LAZ 7/28/2006 GENERALIZATIONS OF THE EXTENSION PRINCIPLE information = constraint on a variable f(X) is A given information about X g(X) is B inferred information about X B ( v ) supu ( A ( f ( u )) subject to: 114 /168 v g( u ) LAZ 7/28/2006 CONTINUED f(X1, …, Xn) is A B ( v ) supu ( A ( f ( u )) g(X1, …, Xn) is B Subject to: B ( v ) supu ( A ( f ( u )) (X1, …, Xn) is A gj(X1, …, Xn) is Yj (Y1, …, Yn) is B 115 /168 v g( u ) , j=1, …, n Subject to: v g( u ) j = 1,..., n LAZ 7/28/2006 EXAMPLE OF DEDUCTION p: Most Swedes are much taller than most Italians q: What is the difference in the average height of Swedes and Italians? Solution Step 1. precisiation: translation of p into GCL S = {S1, …, Sn}: population of Swedes I = {I1, …, In}: population of Italians gi = height of Si , g = (g1, …, gn) hj = height of Ij , h = (h1, …, hn) µij = µmuch.taller(gi, hj)= degree to which Si is much taller than Ij 116 /168 LAZ 7/28/2006 CONTINUED 1 ri j ij = Relative Count of Italians in relation to whom n Si is much taller ti = µmost (ri) = degree to which Si is much taller than most Italians 1 v= t i = Relative Count of Swedes who are m much taller than most Italians ts(g, h) = µmost(v) p generalized constraint on S and I 1 1 i gi j h j q: d = m n 117 /168 LAZ 7/28/2006 CONTINUED Step 2. Deduction via Extension Principle q ( d ) supg ,h ts( g , h ) subject to 1 1 d i gi j h j m n 118 /168 LAZ 7/28/2006 DEDUCTION PRINCIPLE 1. 2. 3. Precisiate query Precisiate query-relevant information Employ constraint propagation (Extension Principle) to deduce the answer to query example q: What is the average height of Swedes? Assume that P is a population of Swedes, P=(Name1, …, Namen), with hi=Height(Namei), i=1, …, n. 119 /168 LAZ 7/28/2006 CONTINUED q 1 (h1+···+hn) n (qri) I: Most Swedes are tall I most 1 (µtall(h1)+···+µtall(hn) is n GC(h): (µmost( hn) 120 /168 1 n (iµtall(hi)) , h = (hi, ···, LAZ 7/28/2006 CONTINUED constraint propagation 1 (µmost( (iµtall(hi)) n Extension Principle 1 Ave(h) = ihi n 1 (µAve(h)(v) = suph(µmost( iµtall(hi)) , n subject to: 121 /168 (h1+···+hn) 1 v = ihi n LAZ 7/28/2006 DEDUCTION PRINCIPLE—GENERAL FORMULATION Point of departure: question, q Data: D = (X1/u1, …, Xn/un) ui is a generic value of Xi Ans(q): answer to q If we knew the values of the Xi, u1, …, un, we could express Ans(q) as a function of the ui Ans(q)=g(u1, …,un) 122 /168 u=(u1, …, un) Our information about the ui, I(u1, …, un) is a generalized constraint on the ui. The constraint is defined by its test-score function f(u)=f(u1, …, un) LAZ 7/28/2006 CONTINUED Use the extension principle Ans( q ) ( v ) supu ( ts( u )) subject to v g( u ) 123 /168 LAZ 7/28/2006 MODULAR DEDUCTION DATABASE POSSIBILITY MODULE SEARCH MODULE 124 /168 PROBABILITY FUZZY ARITHMETIC MODULE agent MODULE FUZZY LOGIC MODULE EXTENSION PRINCIPLE MODULE LAZ 7/28/2006 125 /168 LAZ 7/28/2006 THE CONCEPT OF BIMODAL DISTRIBUTION (ZADEH 1979) X isbm R bimodal distribution random variable A bimodal distribution is a collection of ordered pairs of the form R: {(P1, A1), …, (Pn, An)} or equivalently i(Pi \Ai) , i=1, …, n where the Pi are fuzzy probabilities and the Ai are fuzzy sets 126 /168 LAZ 7/28/2006 CONTINUED Special cases: 1. The Pi are crisp; the Ai are fuzzy 2. The Pi are fuzzy; the Ai are crisp 3. The Pi are crisp; the Ai are crisp 127 /168 The Demspter-Shafer theory of evidence is basically a theory of crisp bimodal distributions LAZ 7/28/2006 EXAMPLE: FORD STOCK 128 /168 I am considering buying Ford stock. I ask my stockbroker, “What is your perception of the near-term prospects for Ford stock?” He tells me, “A moderate decline is very likely; a steep decline is unlikely; and a moderate gain is not likely.” My question is: What is the probability of a large gain? LAZ 7/28/2006 CONTINUED 129 /168 Information provided by my stockbroker may be represented as a collection of ordered pairs: Price: ((unlikely, steep.decline), (very.likely, moderate.decline), (not.likely, moderate.gain)) In this collection, the second element of an ordered pair is a fuzzy event or, equivalently, a possibility distribution, and the first element is a fuzzy probability. The importance of the concept of a bimodal distribution derives from the fact that in the context of human-centric systems, most probability distributions are bimodal LAZ 7/28/2006 BIMODAL DISTRIBUTIONS 130 /168 Bimodal distributions can assume a variety of forms. The principal types are Type 1, Type 2 and Type 3. Type 1, 2 and 3 bimodal distributions have a common framework but differ in important detail LAZ 7/28/2006 BIMODAL DISTRIBUTIONS (Type 1, 2, 3) U A1 An A2 A Type 1 (default): X is a random variable taking values in U A1, …, An, A are events (fuzzy sets) pi = Prob(X is Ai) , i = 1, …, n ipi is unconstrained pi is Pi (granular probability) BMD: bimodal distribution: ((P1, A1), …, (Pn, An)) X isbm (P1\A1 + ··· + Pn\An) Problem: What is the probability, p, of A? In general, this probability is fuzzy-set-valued, that is, granular 131 /168 LAZ 7/28/2006 CONTINUED Type 2 (fuzzy random set): X is a fuzzy-set-valued random variable with values A1, …, An (fuzzy sets) pi = Prob(X = Ai), i = 1, …, n BMD: X isrs (p1\A1 + ··· + pn\An) ipi = 1 Problem: What is the probability, p, of A? p is not definable. What are definable are (a) the expected value of the conditional possibility of A given BMD, and (b) the expected value of the conditional necessity of A given BMD 132 /168 LAZ 7/28/2006 CONTINUED Type 3 (augmented random set; Dempster-Shafer): X is a set-valued random variable taking the values X1, …, Xn with respective probabilities p1, …, pn Yi is a random variable taking values in Ai, i = 1, …, n Probability distribution of Yi in Ai, i = 1, …, n, is not specified X isp (p1\X1+···+pn\Xn) Problem: What is the probability, p, that Y1 or Y2 … or Yn is in A? Because probability distributions of the Yi in the Ai are not specified, p is interval-valued. What is important to note is that the concepts of upper and lower probabilities break down when the Ai are fuzzy sets 133 /168 LAZ 7/28/2006 IS DEMPSTER SHAFER COINTENSIVE? In applying Dempster Shafer theory, it is important to check on whether the data fit Type 3 model. NL description of problem 134 /168 precisiation Bimodal Type 1 precisiation Bimodal Type 2 precisiation Bimodal Type 3 DempsterShafer Caveat: In many cases the cointensive (well-fitting) precisiand (model) of a problem statement is bimodal distribution of Type 1 rather than Type 3 (Demspter-Shafer) LAZ 7/28/2006 BASIC BIMODAL DISTRIBUTION (BMD) (Type 1) (PERCEPTION-BASED PROBABILITY DISTRIBUTION) X is a real-valued random variable probability P3 P2 g P1 X 0 A1 A2 A3 BMD: P(X) = Pi(1)\A1 + Pi(2)\A2 + Pi(3)\A3 Prob {X is Ai } is Pj(i) P(X)= low\small + high\medium + low\large 135 /168 LAZ 7/28/2006 P INTERPOLATION OF A BASIC BIMODAL DISTRIBUTION (TYPE 1) g(u): probability density of X p1 p2 p pn X 0 A1 A2 A An pi is Pi : granular value of pi , i=1, …, n (Pi , Ai) , i=1, …, n are given A is given (?P, A) 136 /168 LAZ 7/28/2006 INTERPOLATION MODULE AND PROBABILITY MODULE Prob {X is Ai} is Pi , i = 1, …, n Prob {X is A} is Q Q ( v ) supg ( P1 ( A1 ( u )g( u )du ) U Pn Pn ( An ( u )g( u )du )) U U subject to U A ( u )g( u )du U 137 /168 LAZ 7/28/2006 EXAMPLE Probably it will take about two hours to get from San Francisco to Monterey, and it will probably take about five hours to get from Monterey to Los Angeles. What is the probability of getting to Los Angeles in less than about seven hours? BMD: (probably, *2) + (probably, *5) X Z = X+Y w 138 /168 Y pz ( w ) p x ( u ) pY ( w u )du u v LAZ 7/28/2006 CONTINUED query: pZ ( w ) * 7 ( w )dw is ?A pX probably ( * 2 ( u ) pX ( u )du ) qri: pY probably ( * 5 ( v ) pY ( v )dv ) A ( t ) suppX , pY ( X Y ) subject to: t p X ( w ) * 7 ( w )dw 139 /168 LAZ 7/28/2006 TEST PROBLEMS (PROBABILITY THEORY) X is a real-valued random variable. What is known about X is: a(usually X is much larger than approximately a; b usually X is much smaller than approximately b, where a and b are real numbers with a < b. What is the expected value of X? X and Y are random variables. (X,Y) takes values in the unit circle. Prob(1) is approximately 0.1; Prob(2) is approximately 0.2; Prob(3) is approximately 0.3; Prob(4) is approximately 0.4. What is the marginal distribution of X? Y 4 3 140 /168 0 1 2 X LAZ 7/28/2006 CONTINUED function: if X is small then Y is large +… (X is small, Y is large) probability distribution: low \ small + low \ medium + high \ large +… Count \ attribute value distribution: 5* \ small + 8* \ large +… PRINCIPAL RATIONALES FOR F-GRANULATION detail not known detail not needed detail not wanted 141 /168 LAZ 7/28/2006 OPERATIONS ON BIMODAL DISTRIBUTIONS P(X) defines possibility distribution of g ( g ) Pi ( U Ai ( u )g( u )du ) Pu ( U An ( u )g( u )du ) problem a) what is the expected value of X 142 /168 LAZ 7/28/2006 EXPECTED VALUE OF A BIMODAL DISTRIBUTION E ( P*) U ug( u )du f ( g ) Extension Principle E ( P *) ( v ) sup ( p1 ( U A1 ( u )g( u )du ) g Pn ( U An ( u )g( u )du )) subject to: 143 /168 v U ug( u )du LAZ 7/28/2006 PERCEPTION-BASED DECISION ANALYSIS ranking of bimodal probability distributions PA 0 X PB 0 maximization of expected utility 144 /168 X ranking of fuzzy numbers LAZ 7/28/2006 USUALITY CONSTRAINT PROPAGATION RULE X: random variable taking values in U g: probability density of X X isu A Prob {X is B} is C X isu A Prob {X is A} is usually ( g ) usually( U A ( u )g( u )du ) C ( v ) supg ( usually( U A ( u )g( u )du )) subject to: 145 /168 v U B ( u )g( u )du LAZ 7/28/2006 PROBABILITY MODULE (CONTINUED) X isp P Y = f(X) Y isp f(P) X isp P (X,Y) is R Y isrs S 146 /168 Prob {X is A} is P Prob {f(X) is B} is Q X isu A Y = f(X) Y isu f(A) LAZ 7/28/2006 PNL-BASED DEFINITION OF STATISTICAL INDEPENDENCE Y contingency table L C(M/L) M C(S/S) S X 0 S M (M/L)= 3 L/S L/M L/L 2 M/S M/M M/L 1 S/S S/M S/L 1 2 3 L C (M x L) C (L) • degree of independence of Y from X= degree to which columns 1, 2, 3 are identical 147 /168 PNL-based definition LAZ 7/28/2006 WHAT IS A RANDOM SAMPLE? In most cases, a sample is drawn from a population which is a fuzzy set, e.g., middle class, young women, adults In the case of polls, fuzziness of the population which is polled may reflect the degree applicability of the question to the person who is polled example (Atlanta Constitution 5-29-95) Is O.J. Simpson guilty? Random sample of 1004 adults polled by phone. 61% said “yes.” Margin of error is 3% to what degree is this question applicable to a person who is n years old? 148 /168 LAZ 7/28/2006 CONJUNCTION X is A X is B X is A B X isu A X isu B X isr A B •determination of r involves interpolation of a bimodal distribution 150 /168 LAZ 7/28/2006 USUALITY CONSTRAINT X isu A X isu B X isp P (A B) ispv Q X is A X is B X is A B g: probability density function of X (g): possibility distribution function of g (g ) supg ( usually( g (u ) A (u )du ) usually( g (u ) B (u )du )) U U subject to: U g (u )du 1 Q (v ) supg ((g )) subject to: v U g (u )( A (u ) B (u ))du 151 /168 LAZ 7/28/2006 USUALITY — QUALIFIED RULES X isu A X isun (not A) X isu A Y=f(X) Y isu f(A) f ( A ) ( v ) supu|v f ( u ) ( A ( u )) 152 /168 LAZ 7/28/2006 USUALITY — QUALIFIED RULES X isu A Y isu B Z = f(X,Y) Z isu f(A, B) Z ( w ) supu ,v |w f ( u ,v ) ( A ( u ) B ( v ) 153 /168 LAZ 7/28/2006 SUMMATION The concept of GC-computation is the centerpiece of NL-computation. The point of departure in NLcomputation is the key idea of representing the meaning of a proposition drawn from a natural language, p, as a generalized constraint. This mode of representation may be viewed as precisiation of p, with the result of precisiation being a precisiand, p*, of p. Each precisiand is associated with a measure, termed cointension, of the degree to which the intension of p* is a good fit to the intension of p. A principal desideratum of precisiation is that the resulting precisiand be cointensive. The concept of cointensive precisiation is a key to mechanization of natural language understanding. The concept of NL-computation has wide-ranging ramifications, especially within human-centric fields such as economics, law, linguistics and psychology 154 /168 LAZ 7/28/2006 155 /168 LAZ 7/28/2006 DEDUCTION THE BALLS-IN-BOX PROBLEM Version 1. Measurement-based A flat box contains a layer of black and white balls. You can see the balls and are allowed as much time as you need to count them q1: What is the number of white balls? q2: What is the probability that a ball drawn at random is white? q1 and q2 remain the same in the next version 156 /168 LAZ 7/28/2006 DEDUCTION Version 2. Perception-based You are allowed n seconds to look at the box. n seconds is not enough to allow you to count the balls You describe your perceptions in a natural language p1: there are about 20 balls p2: most are black p3: there are several times as many black balls as white balls PT’s solution? 157 /168 LAZ 7/28/2006 MEASUREMENT-BASED 158 /168 version 1 a box contains 20 black and white balls over seventy percent are black there are three times as many black balls as white balls what is the number of white balls? what is the probability that a ball picked at random is white? PERCEPTION-BASED version 2 a box contains about 20 black and white balls most are black there are several times as many black balls as white balls what is the number of white balls what is the probability that a ball drawn at random is white? LAZ 7/28/2006 COMPUTATION (version 2) 159 /168 measurement-based X = number of black balls Y2 number of white balls X 0.7 • 20 = 14 X + Y = 20 X = 3Y X = 15 ; Y=5 p =5/20 = .25 perception-based X = number of black balls Y = number of white balls X = most × 20* X = several *Y X + Y = 20* P = Y/N LAZ 7/28/2006 FUZZY INTEGER PROGRAMMING Y X= most × 20* X+Y= 20* X= several × y 1 160 /168 x LAZ 7/28/2006 January 26, 2005 Factual Information About the Impact of Fuzzy Logic PATENTS 161 /168 Number of fuzzy-logic-related patents applied for in Japan: 17,740 Number of fuzzy-logic-related patents issued in Japan: 4,801 Number of fuzzy-logic-related patents issued in the US: around 1,700 LAZ 7/28/2006 PUBLICATIONS Count of papers containing the word “fuzzy” in title, as cited in INSPEC and MATH.SCI.NET databases. Compiled by Camille Wanat, Head, Engineering Library, UC Berkeley, December 22, 2004 Number of papers in INSPEC and MathSciNet which have "fuzzy" in their titles: INSPEC - "fuzzy" in the title 1970-1979: 569 1980-1989: 2,404 1990-1999: 23,207 2000-present: 14,172 Total: 40,352 MathSciNet - "fuzzy" in the title 1970-1979: 443 1980-1989: 2,465 1990-1999: 5,483 2000-present: 3,960 Total: 12,351 162 /168 LAZ 7/28/2006 JOURNALS 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 163 /168 (“fuzzy” or “soft computing” in title) Fuzzy Sets and Systems IEEE Transactions on Fuzzy Systems Fuzzy Optimization and Decision Making Journal of Intelligent & Fuzzy Systems Fuzzy Economic Review International Journal of Uncertainty, Fuzziness and Knowledge-Based Systems Journal of Japan Society for Fuzzy Theory and Systems International Journal of Fuzzy Systems Soft Computing International Journal of Approximate Reasoning--Soft Computing in Recognition and Search Intelligent Automation and Soft Computing Journal of Multiple-Valued Logic and Soft Computing Mathware and Soft Computing Biomedical Soft Computing and Human Sciences Applied Soft Computing LAZ 7/28/2006 APPLICATIONS The range of application-areas of fuzzy logic is too wide for exhaustive listing. Following is a partial list of existing application-areas in which there is a record of substantial activity. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. Industrial control Quality control Elevator control and scheduling Train control Traffic control Loading crane control Reactor control Automobile transmissions Automobile climate control Automobile body painting control Automobile engine control Paper manufacturing Steel manufacturing Power distribution control Software engineerinf Expert systems Operation research Decision analysis 164 /168 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. Financial engineering Assessment of credit-worthiness Fraud detection Mine detection Pattern classification Oil exploration Geology Civil Engineering Chemistry Mathematics Medicine Biomedical instrumentation Health-care products Economics Social Sciences Internet Library and Information Science LAZ 7/28/2006 Product Information Addendum 1 This addendum relates to information about products which employ fuzzy logic singly or in combination. The information which is presented came from SIEMENS and OMRON. It is fragmentary and far from complete. Such addenda will be sent to the Group from time to time. SIEMENS: * washing machines, 2 million units sold * fuzzy guidance for navigation systems (Opel, Porsche) * OCS: Occupant Classification System (to determine, if a place in a car is occupied by a person or something else; to control the airbag as well as the intensity of the airbag). Here FL is used in the product as well as in the design process (optimization of parameters). * fuzzy automobile transmission (Porsche, Peugeot, Hyundai) OMRON: * fuzzy logic blood pressure meter, 7.4 million units sold, approximate retail value $740 million dollars Note: If you have any information about products and or manufacturing which may be of relevance please communicate it to Dr. Vesa Niskanen [email protected] and Masoud Nikravesh [email protected] . 165 /168 LAZ 7/28/2006 Product Information Addendum 2 This addendum relates to information about products which employ fuzzy logic singly or in combination. The information which is presented came from Professor Hideyuki Takagi, Kyushu University, Fukuoka, Japan. Professor Takagi is the co-inventor of neurofuzzy systems. Such addenda will be sent to the Group from time to time. Facts on FL-based systems in Japan (as of 2/06/2004) 1. Sony's FL camcorders Total amount of camcorder production of all companies in 1995-1998 times Sony's market share is the following. Fuzzy logic is used in all Sony's camcorders at least in these four years, i.e. total production of Sony's FL-based camcorders is 2.4 millions products in these four years. 1,228K units X 49% in 1995 1,315K units X 52% in 1996 1,381K units X 50% in 1997 1,416K units X 51% in 1998 2. FL control at Idemitsu oil factories Fuzzy logic control is running at more than 10 places at 4 oil factories of Idemitsu Kosan Co. Ltd including not only pure FL control but also the combination of FL and conventional control. They estimate that the effect of their FL control is more than 200 million YEN per year and it saves more than 4,000 hours per year. 166 /168 LAZ 7/28/2006 3. Canon Canon used (uses) FL in their cameras, camcorders, copy machine, and stepper alignment equipment for semiconductor production. But, they have a rule not to announce their production and sales data to public. Canon holds 31 and 31 established FL patents in Japan and US, respectively. 4. Minolta cameras Minolta has a rule not to announce their production and sales data to public, too. whose name in US market was Maxxum 7xi. It used six FL systems in a camera and was put on the market in 1991 with 98,000 YEN (body price without lenses). It was produced 30,000 per month in 1991. Its sister cameras, alpha-9xi, alpha-5xi, and their successors used FL systems, too. But, total number of production is confidential. 167 /168 LAZ 7/28/2006 5. FL plant controllers of Yamatake Corporation Yamatake-Honeywell (Yamatake's former name) put FUZZICS, fuzzy software package for plant operation, on the market in 1992. It has been used at the plants of oil, oil chemical, chemical, pulp, and other industries where it is hard for conventional PID controllers to describe the plan process for these more than 10 years. They planed to sell the FUZZICS 20 - 30 per year and total 200 million YEN. As this software runs on Yamatake's own control systems, the software package itself is not expensive comparative to the hardware control systems. 6. Others Names of 225 FL systems and products picked up from news articles in 1987 - 1996 are listed at http://www.adwin.com/elec/fuzzy/note_10.html in Japanese.) Note: If you have any information about products and or manufacturing which may be of relevance please communicate it to Dr. Vesa Niskanen [email protected] and Masoud Nikravesh [email protected] , with cc to me. 168 /168 LAZ 7/28/2006