examples of semantic coordination. typology of semantic updates

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Examples of semantic coordination

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Page 1: Examples of semantic coordination. Typology of semantic updates

Examples of semantic coordination

Page 2: Examples of semantic coordination. Typology of semantic updates

Typology of semantic updates

Page 3: Examples of semantic coordination. Typology of semantic updates

Theory development:Kinds of semantic coordination

• Concept-level coordination: Coordinating available concepts (meanings)– Modify existing concept– Create new concept

• Register-level coordination: Coordinating on a register, i.e. a vocabulary (set of expressions), an ontology (concept system), and a mapping between them– Select one of several predefined registers to use– Create new register

• Mapping a vocabulary onto an existing ontology• Mapping a vocabulary onto a new ontology: may involve concept-

level coordination

• (Feature-level coordination: modify globally available feature set)

Page 4: Examples of semantic coordination. Typology of semantic updates

Kinds of representations & updates

Representations Updates

record type semantics (Cooper) coercion of record types

predicate logic / lambda calculus semantic composition (“porch” example?)

neural networks (Steels) update neural net weights

vector space models modify vectors in vector space model

hybrid representations complex updates

Page 5: Examples of semantic coordination. Typology of semantic updates

Feedback

Page 6: Examples of semantic coordination. Typology of semantic updates

Corrective feedback

Page 7: Examples of semantic coordination. Typology of semantic updates

• is it really a correction? can also be seen as providing more specific information– in this case, no revision of bear

• but why would B say ”panda” unless B thinks it is more appropriate?– social norm: use same term if possible

• but perhaps too strong to say ”bear” is inappropriate;– just that ”panda” is more appropriate

• counterexample?– A ”It’s a nice drink”– B ”Yes, it’s a nice Darjeeling”

• so, only corrective under certain circumstances?– ambiguous between corrective and non-corrective use?

Page 8: Examples of semantic coordination. Typology of semantic updates

Representations and updates:Semantic features and updates

• Semantics using features and values– Usage pattern = set of concepts (polysemy)

• [bear] = { bear-animal, bear-toy }– Concept = record types

• Panda = [ x: Ind, c1: animate(x), c2: bw(x) ]• Animate = [ x: Ind, c: animate(x) ]• predicate panda

– panda(a) if (Er:Panda & r.x = a)• (could make “panda” detector predicate by building PANDA detector, from

BW and ANIMATE detectors)– do abstract or concrete predicates have detectors? which are created first in

children? what happens then – abstrction or concretion? functional equivalance

– Global feature set = all possible features, given by model• “detector” predicates: animate, bw• detectors: ANIMATE, BW• animate(x) if ANIMATE(x.1)

Page 9: Examples of semantic coordination. Typology of semantic updates

• Feature-value update– Modify value of feature

• bear-animal.colour := (brown OR black)• Bear : [ x:Ind, c: brown(x), ... ]• Bear.c := brown(x) OR black(x)

– Requires dynamic types in record types• if T1 and T2 are types, T1 OR T2 is a type• create “Join type” Bear’ = [ x: Ind, c: brown(x) ] OR [x: Ind, c:

black(x)]• simplify Bear’ to [ x: Ind, c: brown(x) OR black(x) ] • Bear.c := Bear’.c

– (idea: apply(Bear, c, ly.y OR black(R.x) ])

Page 10: Examples of semantic coordination. Typology of semantic updates

• Concept-feature update– Add/delete feature for concept

• addFeature(bear-animal.habitat : Habitat)– Requires dynamic local feature set

• Meaning-concept update– Add/remove concept from usage pattern– Requires dynamic set of concepts

• Concept and meaning creation• panda-animal := { animate = 1, colour = ( black AND white ) }• [panda] := { panda-animal }

• Global feature set update– create / modify / delete global feature– Requires dynamic global feature set

Page 11: Examples of semantic coordination. Typology of semantic updates

• panda type inherits from bear type, by adding panda as subype of bear, modify COLOUR of bear to include black-and-white

• alt: panda type created by modifying bear type (COLOUR value of panda different from that of bear)

• meanings in terms of records based on OWL ontology– [x:panda-animal] if [ x: Ind, c1: animate(x), c2: colour(x, black-and-white) ]– x:panda-animal panda-animal(x)– panda-animal = (lx:[ x: Ind, c1: animate(x), c2: colour(x, black-and-white) ])[c3:panda-

animal(x)]

– Panda:[ x: Ind, c1: animate(x), c2: colour(x, black-and-white) ]– panda(a) if (Er:Panda & r.x = a)

– short version: a::R iff Er:R & r.x=a

– ”the panda is nice” [x:ind, c1:panda(x), c2:nice(x)]– panda(x) is appropriate of x:Panda– connection predicate ”panda” – type ”Panda”???

– NOT same as (Er:Panda & r.x = a):panda(a)

Page 12: Examples of semantic coordination. Typology of semantic updates

• Panda:[ x: Ind, c1: animate(x), c2: colour(x, black-and-white) ]• panda(a) if (Er:Panda & r.x = a)• panda(x) if [x:Ind, r:Panda, c:eq(Ind, x, r.x)]• a:panda(a) iff Er:Panda & r.x=a

• shared context: [a:Ind]• A’s bear-detector outputs 1 when directed to a• -> A has model <{a}, F>• A: that’s a nice bear

– [c1:bear(a), c2:nice(a)• (assuming this is a correction)• A’s bear-detectour outputs 0, but panda-detector outputs 1• B: yes, it’s a nice panda

– [c3:panda(a)]• A modifes bear-detector to output 0 when directed to a

– e.g. by modifyíng value feature ”colour”• A creates a panda-detector

• Panda-detector?• record type supported if there is a way of creating records of that type

Page 13: Examples of semantic coordination. Typology of semantic updates

• -> A has model <{a}, F>

• F provides proofs• F(panda(a))=panda-detector(a, 1)• panda(x) requires colour(x,bw)• panda-detector(x,1) requires colour-detector(x, bw, 1)

• [ x = a, c = PDa ] panda(a)???• [ x=a, c = BW(a) ] bw(a)

– BW = black-and-white-detector• F(bw(a)) = BW(a,1)• ”a is black and white” Er:[x:Ind, c:bw(x)] & a=r.x• Er:R means ”the record type R is supported by r in the model if r can be created”• assume we have detectors BW and ANIMATE• F(animate(a)) = ANIMATE(a,1)• ? panda(a)

– Panda =[ x: Ind, c1: animate(x), c2: bw(x) ]– panda(a) if (Er:Panda & r.x = a)– ? Er:[ x: Ind, c1: animate(x), c2: bw(x) ]&r.x=a– in model: ? a in F(Ind) & ANIMATE(a,1) & BW(a,1)

Page 14: Examples of semantic coordination. Typology of semantic updates

• Panda =[ x: Ind, c1: animate(x), c2: bw(x) ]

• panda(a) if (Er:Panda & r.x = a)

• ? Er:[ x: Ind, c1: animate(x), c2: bw(x) ]&r.x=a

• [ x = a, c1 = ANIMATE(a,1), c2 = BW(a,1)]

• ANIMATE(x,1) : animate(x) [this mapping done by F]

Page 15: Examples of semantic coordination. Typology of semantic updates

”X-och-X”

• ”X-och-X”-konstruktionen kodas som icm:challenge_use(X)

• Example (Lindström 1996, 2001)– L: du har haft många inspelade samtal eller?

• ask(”F har haft många inspelade samtal?”)

– F: nja, många och många, men de e nåra stycken• icm:challenge_use(”många”)

– MAX-QUD: ?x.replaces(x, ”många”)– S-[”många”] :=+ s

• icm:replace(”många”, ”några stycken”)– FACTS = { ”F har haft några (stycken) inspelade samtal”, … }– S+[”några stycken”] :=+ s

Page 16: Examples of semantic coordination. Typology of semantic updates

• Exempel:– B: du har drivhus?

• ask(”A har drivhus?”)

– A: ja, drivhus och drivhus, ja sår små frön så kommer dom upp

• icm:challenge_use(”drivhus”)– MAX-QUD:?x.replaces(x, ”drivhus”)– S+[”drivhus”] :=- s

• icm:replace(”A har drivhus”, ”A sår små frön så kommer dom upp”)

– accommodate ?x.replaces(x,”A har drivhus”)– S-([”drivhus”]) :=+ s

Page 17: Examples of semantic coordination. Typology of semantic updates

• Exempel:– A: (…) där han söker efter ord väldigt länge.

(.) eller väldigt å väldigt länge, de tar i alla fall rätt lång tid

• assert(”(han) söker efter ord väldigt länge”)• icm:challenge_use(”väldigt”)• icm:replace(”A gör H väldigt länge”,”H (utförd av A)

tar lång tid”)

Page 18: Examples of semantic coordination. Typology of semantic updates

Accommodation

Page 19: Examples of semantic coordination. Typology of semantic updates

Contextual interpretation and update: Example

• [”two o’clock”] = { [”two o’clock”]clock , [”two o’clock”]dir-giv}– ”clock” activity (basic) > 02:00 AM or PM– ”direction-giving” activity > East-norteast direction

• In the Map task activity, A utters "sort of two o'clock“• B activates [”two o’clock”]dir-giv

B

• B instantiates [”two o’clock”]dir-givB

to arrive at a contextual interpretation [”two o’clock”]s

B

• [“two o’clock”]dir-givB ○=

+ [“two o’clock”]sB

– Assuming [“two o’clock”]direction-givingB ⊦ s

Page 20: Examples of semantic coordination. Typology of semantic updates

Accommodation: example

• Assume [”two o’clock”]B = { [”two o’clock”]Bclock }

• A, in Map Task situation: "sort of two o'clock“• We have [“two o’clock”]B ⊬ s• Assume B makes situated interpretation [”two o’clock”]s

B

• We get [“two o’clock”]B ○*+ [“two o’clock”]s

B – create [“two o’clock”]dir-giv

B – [”two o’clock”]B = { [”two o’clock”]B

clock, [“two o’clock”]dir-givB

}

– [“two o’clock”]dir-givB ○=

+ [“two o’clock”]sB

• After this, [“two o’clock”]dir-givB ⊦ s

• And consequently, [“two o’clock”]B ⊦ s

Page 21: Examples of semantic coordination. Typology of semantic updates

Accommodation, Compositional update (discrete)

Page 22: Examples of semantic coordination. Typology of semantic updates

Meaning accommodation, cont’d

• Example– Jules: On my paper round this morning I porched all the papers

without getting off my bike!– Jim: Congratulations.

• Jules uses “porch” in a situation s to mean approximately “successfully throw onto a porch”

• This is a common usage for Jules: [“porch”]Jules ⊦ s• B is not familiar with this use: [“porch”]Jim ⊬ s • In this case, Jim was able to create a situated

interpretation by using contextual cues, world knowledge, commonsense background, and the ability to reason by analogy and metaphor. – [“porch”]s

Jim

Page 23: Examples of semantic coordination. Typology of semantic updates

Meaning accommodation, cont’d

• Also, Jim chooses to accept this novel use of “porch” and provides feedback displaying understanding and acceptance

• This thus counts as a case of accommodated conservative use in the table on the previous slide

• As a consequence (or so our theory predicts) the corresponding updates are made– [“porch”]Jim ○*

+ [“porch”]sJim

• (Note that Jules’ judgement of appropriateness may have taken into account Jules’ beliefs about Jim’s ability to understand “porch” in this way)

Page 24: Examples of semantic coordination. Typology of semantic updates

Explicit negotiation• If Jim had not been able to understand Jules' use of “porch”, or if

Jim had understood it but not accepted it, explicit negotiation would be expected– B: “What do you mean, porch”?– A: “Like, you know, throwing it onto the porch”

• Typically, triggered by negative feedback, clarification requests – In general, in cases where a use is rejected or not understood

(unsuccessful uses), explicit negotiation of the meaning and proper usage of c may well occur

• Explicit negotiation = overt meta-linguistic negotiation of the proper usage of words, including e.g. cases where explicit verbal or ostensive definitions are proposed (and possibly discussed)

• Although semantic negotiation typically has the goal of coordinating language use, it may in general be either antagonistic or cooperative

Page 25: Examples of semantic coordination. Typology of semantic updates

Explicit negotiation

Page 26: Examples of semantic coordination. Typology of semantic updates

Ostensive definitionIncremental updates

• Steels and Belpaeme (2004) investigate the effect of social linguistic interaction on learning and coordination of colour categories.

– Robot agents play a language game of referring to and pointing to colour samples.

– The language system of an individual agent is modelled as a set of categories in the form of neural nets that respond to sensory data from colour samples, and a lexicon connecting words to categories.

• This is clearly a case of semantic plasticity and semantic negotiation, as categories are updated as a result of language use.

• Semantic negotiation here takes the form of explicit and cooperative negotiation.

• There is also an asymmetry with respect to the roles within each game; one agent is speaker and the other is the hearer.

• The interaction follows a predefined ``guessing game'' script; essentially, a language game of guessing and ostensive definition.

• The situation, as perceived by the agents, is a set of objects (colour samples), where one is the topic object.

Page 27: Examples of semantic coordination. Typology of semantic updates

Ostensive definition, cont’d• Below is a possible interaction between two agents playing the guessing

game, and the corresponding updates in terms of the model presented in this paper.

• The context is O a set of object (colour samples), – O = {o1, …, oN} where one object ot is the focus object.

• The speaker (A) knows which object is the focus object but the hearer (B) does not.

• The goal of the game is for B to correctly identify ot from O based on the interaction with A

• A will first utter the word (here: “wabaku”) that A associates with ot, i.e. the word associated to the semantic category (in the form of a neural network) that uniquely discriminates ot

• In terms of our framework, we identify the neural network with the usage pattern, which for the speaker is– [“wabaku”]A

– Concretely, the usage pattern is stored as an array of numbers representing weights in the neural network

Page 28: Examples of semantic coordination. Typology of semantic updates

“Guessing game” (Steels & Belpaeme 2005) as FSA

S: (points to topic)

S: “x”S: fb-acc-pos

H: fb-und-neg

H: (points to assumed topic)

S: fb-acc-neg + (points to topic)

Negotiation of meaning of colour terms through an ostensive language game

A: blueB: (points to colour sample X)A: no (points to colour sample Y)

Page 29: Examples of semantic coordination. Typology of semantic updates

Ostensive definition, cont’d

• A starts off the dialogue game– A: wabaku

• B now looks up ``wabaku'' in its own lexicon and finds an associated semantic category [“wabaku”]B

• B then produces a situated interpretation – [“wabaku”]s

B

– given the architecture of agents in this experiment, this is equivalent to B's sensory impression of an object (og) that B (in this example) is able to uniquely pick out from the context using the semantic category (neural network) [“wabaku”]B

• A then gives feedback to check whether this interpretation is correct.– B: (points at object og)

Page 30: Examples of semantic coordination. Typology of semantic updates

Ostensive definition, cont’d• Unfortunately, B has made a wrong guess, which leads to negative

feedback and a correction:– A: (feedback indicating rejection of B's answer)– A: (points to topic object ot)

• B will now produce a new situated interpretation – [“wabaku”]s

B' = (the sensory impression from) object ot

• As a consequence of this game of semantic negotiation, B will then revise its meaning-pattern (neural network) [“wabaku”]B by adjusting it to better match this new situated meaning; in our theory– [“wabaku”]B ○*

+ [“wabaku”]sB'

• Note that accommodation is not an option in this game– the context is not rich enough to allow the hearer to infer the intended

referent in problematic situations without consulting the speaker– (accommodation requires redundancy)

Page 31: Examples of semantic coordination. Typology of semantic updates

Providing definitions(Second language learners)

• Exempel (Varonis & Gass 1985)– A: kött i Sverige mycke annelunda

• U

– B: mycke?• I

– A: mycke annelunda• R

– B: annolunda?• I

– A: smakar inte samma• R

– B: ahh• RR

Page 32: Examples of semantic coordination. Typology of semantic updates

Second language learners• Exempel (Varonis & Gass 1985)

– A: kött i Sverige mycke annelunda• assert(”kött i Sverige (är) mycket annorlunda”)

– B: mycke?• icm:per*neg:follows(”mycke?”)

– A: mycke annelunda• icm:repeat(”mycket annelunda”)

– B: annolunda?• icm:sem*neg:”annolunda”

– MAX-QUD= ?x.meaning(”annolunda”,X)

– A: smakar inte samma• answer(”smakar inte samma”) / icm:provide_definition(”smakar inte samma”)

– interpreted (in light of MAX-QUD) as » definition(”annolunda”, ”smakar inte samma”)

– this resolves ?x.meaning(”annolunda”,X)

• defs([”annorlunda”]) :=+ ”smakar inte samma”

– B: ahh• icm:acc*pos

Page 33: Examples of semantic coordination. Typology of semantic updates

• What is a definition?– It connects a term with the other terms of the situlect,

and possible superordinate situlects• It adds to the ”theory”• Does not extend usage sets directly but via definition

– The corresponding usage set update is • S+([”annorlunda”], context:food_property) :=U S+[”smakar inte samma”]• I.e. extend the set of appropriate uses of ”annorunda” in the context of

assigning properties to food with the appropriate-set for ”smakar inte samma”

Page 34: Examples of semantic coordination. Typology of semantic updates

Register coordination

Page 35: Examples of semantic coordination. Typology of semantic updates

Implementation:Ontological Coordination in City Navigation

• S: Danny's deli is just north of your current location. – [absolute spatial ontology: north etc.]

• U: uh. I don't know where that is!• S: Turn to face the church. Walk straight ahead for one

block, then make a right turn and walk 50 meters. – [blocks, buildings and streets ontology]

• U: Oh it's on High Street? – [user adapts and switches to street-name ontology]

• S: No. It's on South Bridge, number 45 – [adapt to using street-name ontology]

• U: Sorry, I don't know where South Bridge is.

Page 36: Examples of semantic coordination. Typology of semantic updates

Implementation:Ontological Coordination in City Navigation

• S: Danny's deli is on Clerk Street, near the bridge in the city centre– [different street-name ontology]– South Bridge and Clerk Street are different sections of the same street,

but the whole street is sometimes referred to as Clerk Street• U: Sorry, I don't get it• S: Turn to face the church and walk along Meadow street towards

the north, then at the junction to Clerk Street make a right turn and walk along Clerk Street for about 50 meters until it changes name into South Bridge, then continue on South bridge until you reach number 45. – [combining several micro-ontologies in one utterance]

• U: You lost me there• S: Have a look at this map and follow the direction arrow

– [using alternative spatial ontology for multimodal interaction; talking about maps and arrows]