alignment in human-human and human-computer interactions

Alignment in human-human and human-computer

interactionsHolly Branigan

Jamie Pearson

University of Edinburgh

Holly Branigan & Jamie PearsonHow People Talk To Computers Workshop Hansewissenschaftskolleg 22nd April 2006

Collaborators

University of Edinburgh

• Martin Pickering

Stanford University

• Clifford Nass

• John Hu


Outline• Our approach

• Features of Human-Human interaction (HHI)– Audience design

– Alignment• Patterns of alignment

• Explanations for alignment

• Relevance to HCI

• Methodology for studying HCI

• Data from experiments investigating lexical/syntactic alignment in HCI


Our approach

• Psycholinguistic accounts of HHI:– Characterising linguistic behaviour

– Identifying underlying psychological mechanisms• Focus on lexical and syntactic processing

• Applying to HCI:– Predicting human (user) behaviour

– Simulating human behaviour

– Modifying human behaviour


Features of HHI

• Linguistic behaviour in HHI is highly flexible and adaptive:– An individual speaker’s behaviour is partially

contextually-determined.

– Linguistic choices (semantic, lexical, syntactic, phonological..) choices may vary according to context.

– Relevance to HCI:• Features of HCI communicative context may influence

linguistic behaviour.


Determinants of Behaviour

• Influence of addressee on speaker:• Indirectly – speaker’s beliefs about

addressee’s state of knowledge, interests etc– Audience Design

• Directly – via addressee’s own linguistic behaviour

– Alignment

• Both influences may be active simultaneously


Audience Design• Tailoring utterance to fit addressee:

– Their knowledge, interests, beliefs etc

• May be based on speaker’s a priori beliefs or assumptions about addressee

• Or may be based on direct evidence from addressee– E.g., addressee’s feedback


Audience Design – lexical choice• Fussell & Krauss (1992):

– speakers adjust their choice of lexical terms to fit the assumed knowledge of their addressees:

• Proper names when addressee likely to know referent:

Clint Eastwood

• More detailed descriptions when addressee less likely to know referent:

Media mogul, was married to Jane Fonda, owns CNN, has a moustache and grey hair

– Assessment of addressee knowledge is based on a priori judgements about social distribution of knowledge

• movie stars > industrialists


Audience Design – lexical choice• Isaacs & Clark (1987):

– A priori assessment of addressee knowledge can be rapidly adjusted on basis of direct evidence from feedback

• Lexical choices then reflect this adjusted assessment

– ‘experts’ in a domain (New York landmarks) quickly adjust their choice of lexical terms to fit the apparent expertise of their addressees:

– Proper names when addressee is apparently fellow expert

Chrysler building

– More detailed descriptions when addressee is apparently non-expert

Building with a tall pointy roof and a spike on top


Audience Design - syntax• Audience design may influence syntactic choices:

– Speakers may choose syntactic structures that are most easily understood by addressees.

• Ambiguity-avoidance:

Put the penguin in the cup on the star vs

Put the penguin that’s in the cup on the star

When two penguins (and an empty cup), temporary ambiguity at penguin in the cup…


Audience Design - syntax• Audience design may influence syntactic choices:

– Speakers may choose syntactic structures that are most easily understood by addressees.

• Ambiguity-avoidance:

Put the penguin in the cup on the star vs

Put the penguin that’s in the cup on the star

When two penguins (and an empty cup), temporary ambiguity at penguin in the cup…

Speakers include that’s more often (removing ambiguity) when there are two

penguins than where is only one penguin.

Haywood, Pickering & Branigan (2005)


Audience Design - summary• Speakers in HHI may engage in strategic planning

of aspects of utterances:

– Calculations of addressee knowledge, beliefs etc

– Based on a priori assumptions or direct evidence

• A priori assumptions are quickly updated in light of direct evidence; audience design reflects this

– Strategic planning may affect lexical choice, syntax, semantic choices

• E.g., choice of reference frame (Schober, 1993)


Alignment• Speakers are affected directly by addressee’s

linguistic behaviour:– Tendency for speakers in a dialogue to converge linguistic

behaviour.

– After hearing an interlocutor use particular linguistic behaviour, speakers tend to repeat that behaviour.

– This tendency towards alignment is robust and highly pervasive.

• Rhetorical structure, semantic structure, syntactic structure, lexical choice, accent, speech rate, ….


Alignment• Alignment can be implicit:

– Almost always arises without explicit negotiation• Speakers often align on different expression than negotiated

expression

– Speakers usually unaware of effects• Can sometimes (but often cannot) report awareness of

meaning-related alignment

• Usually unaware of alignment of form


Alignment – semantic choices• Alignment occurs for aspects of language

associated with meaning:

– e.g. reference frames (Watson, Pickering & Branigan, 2005)

The dot is left of the camera vs The dot is below the camera


Alignment – semantic choices• Alignment occurs for aspects of language

associated with meaning:

– e.g. reference frames (Watson, Pickering & Branigan, 2005)

The dot is left of the camera vs The dot is below the camera

– e.g., description schemas (Garrod & Anderson, 1987)

I’m at B5 vs I’m two along and two up


Alignment – lexical choice• Also alignment of lexical choice:

– Use same words in same ways

– box vs node

– square = single node vs configuration of nodes


Alignment – lexical choice• May align on unusual/rare lexical choice:

– e.g., if first person to name object is a non-native speaker




Rocking chair




Rocking chair

The chair that can go back and forth




Rocking chair

The chair that can go back and forth

You can shake your body

Bortfeld & Brennan, 1997


Alignment• Alignment at semantic and lexical levels may be

linked to different types of meaning:– Alignment of perspectives on a situation (ways of thinking

about the world)

– E.g., rainbow trout vs coloured fish

• But other alignment seems to be unrelated to convergence on types of meaning– e.g., speech rate

– e.g, syntax (alternatives express same meaning)


Alignment – syntactic choices



The artist is selling the dancer the gun (Double Object)

vs

The artist is selling the gun to the dancer (Prepositional Object)



The artist is selling the dancer the gun (Double Object)

vs

The artist is selling the gun to the dancer (Prepositional Object)

A: The chef handing the book to the teacher

B: The artist selling the gun to the dancer


Branigan et al. (2000)• Picture-description/-matching game

– Stooge and naïve subject alternately describe pictures

– Stooge produces scripted descriptions (50% PO, 50% DO)

• Stooge describes source picture to subject:

– The nun showing the monk the banana

• Subject chooses matching picture:

– Yup


Branigan et al. (2000)• Picture-description/-matching game

– Stooge and naïve subject alternately describe pictures– Stooge produces scripted descriptions (50% PO, 50% DO)

• Stooge describes source picture to subject: – The nun showing the monk the banana

• Subject chooses matching picture:– Yup

• Subject describes target picture to matcher:– The artist selling the dancer the gun

• Matcher chooses matching picture:– Uh huh


Confederate-scripting paradigm

Confederate’s script

Naïve participant

Picture cards to be matched

Confederate

Bla

h

Bla

h

Bla

h

Branigan et al (2000)


Alignment - syntax• Strong tendency to align syntax with interlocutor:

– More likely to produce a Prep Obj description after hearing a Prep Obj description than after a Double Obj description, and vice versa.

– 77% aligned descriptions when verb repeated

– 63% aligned descriptions when verb not repeated• Chance = 50%

– NB: speakers align sentence form: both alternatives have same denotational meaning

• (cf. semantic/lexical alignment)

– Speakers align dynamically (produce both PO and DO)


Alignment - syntax• Similar effects found:

– for other structures:• E.g., NP structure: a red cat vs a cat that’s red (Cleland &

Pickering, 2003)

– NB: Relative clause = strongly dispreferred in null context

– in multi-party dialogues:• Speakers syntactically align, whether directly addressed or

not.

A: The waitress is giving the monk the banana

C: Yup



– for other structures:• E.g., NP structure: a red cat vs a cat that’s red (Cleland &

Pickering, 2003)– NB: Relative clause = strongly dispreferred in null context

– in multi-party dialogues:• Speakers syntactically align, whether directly addressed or

not.

A: The waitress is giving the monk the bananaC: Yup

B: The teacher is handing the cowboy the jugC: Uh huh

Branigan et al. (in press)



– in different communicative contexts:• e.g., during walkie-talkie communication

– in ‘special’ populations such as bilinguals, L2 learners, children…





El cerdo llora El pingüino baila (SV)





El cerdo llora El pingüino baila (SV)

Llora el cerdo Baila el pingüino (VS)

Flett, Branigan & Pickering, in prep


Alignment - summary• Alignment with addressee’s linguistic behaviour:

– is robust

– can be very strong determinant of behaviour

– occurs for many (all?) levels of linguistic structure

– occurs for aspects of structure concerned with form, not just meaning


Alignment and audience design• Alignment and audience design may co-occur.

Put the penguin in the cup… vs the penguin that’s in the cup…


Alignment and audience design• Alignment and audience design may co-occur.

Put the penguin in the cup… vs that’s in the cup…

– Priming: • tendency to say The penguin that’s in the cup after hearing

The sheep that’s on the plate

– Audience design:• tendency to say The penguin that’s in the cup when there are two

penguins Haywood, Pickering & Branigan, 2005


Explanations of alignment• Social psychological approaches to alignment:

– Identification with a particular social group (inc. addressee)

– Reciprocity effects (linked to politeness norms?)

– Such approaches explain why alignment of linguistic form occurs (in absence of meaning differences)

– Perceived social identity of addressee is important• e.g., politeness is only relevant for addressees that are

perceived as social agents


Explanations of alignment• Alignment as audience design:

– Alignment may reflect strategic effects (choosing to adopt other person’s perspective to enhance communication)

– Choosing e.g., the same description schema or referential expression maximises the chances of effective communication

– Such approaches do not really explain why alignment of linguistic form occurs (in absence of meaning differences)

– Perceived identity of addressee is important• e.g., depends on addressee being intentional agent

• inanimate entities do not have perspectives or beliefs


Explanations of alignment• Alignment as an automatic behaviour:

– Primitive, default behaviour

– children:

• align significantly more than adults (e.g., NP structure: 75% vs 30%)

• tend to align form, even when this leads to misunderstanding: – e.g., using same term with different reference (e.g., square)

• must learn to suppress tendency towards alignment where appropriate (Garrod & Clark, 1994).


Explanations of alignment• Alignment may be based on automatic priming

mechanisms:• activation-based account (Branigan et al., 2000)

– comprehension of word or structure activates associated linguistic representations

» VP V NP PP

– representations retain residual activation

– residual activation facilitates subsequent selection


Explanations of alignment• Alignment may be fundamental to efficient communication

(Pickering & Garrod, 2004)

• Efficient communication arises when interlocutors come to have the same understanding of relevant aspects of the world.

– This arises from alignment of their situation models (e.g., Zwaan & Radvansky, 1998).

– Alignment of situation models arises from alignment of other aspects of language (e.g., syntax, lexical choice).

• Alignment at one level promotes alignment at others

Lexical alignment syntactic alignment semantic alignment


Explanations of alignment• Explanations are not mutually exclusive: multiple

factors may underline alignment.

– Most likely that at least some implicit element• Participants generally report lack of awareness of alignment

– But other factors may also contribute to overall effect:• Basic (automatic) alignment effect may be enhanced by e.g.

social factors (e.g., social status)

• Alignment at some levels of structure may be differentially susceptible to additional influences


Implications for HCI• Does alignment occur in HCI?

– Pickering & Garrod (2004):• alignment is fundamental to effective communication

– So evidence that alignment is absent in HCI would imply that HCI is necessarily ineffective/inefficient.

• May highlight inherent difficulties in HCI

– Conversely, evidence that alignment is present in HCI suggests possibility of effective communication in HCI


Alignment in HCI?• Why might we expect alignment in HCI?

– Alignment seems to be a default linguistic behaviour:• May be consequence of architecture of human language

processor

• Might therefore expect to find it in any communicative context

– Existing evidence that people treat computers as social actors Reeves & Nass (1996)

• They interact with them and evaluate them as they do other people

People should align with computers


Leveraging alignment in HCI• Alignment may be useful behaviour:

– Facilitates predictions of user behaviour• Reduces decision space in e.g., speech recognition

– Allows simulation of human behaviour

• Users may feel more comfortable with systems that display human-like behaviour

• Users might feel more positively towards systems that align than those that do not

– May allow [implicit] modification of human behaviour• Users may modify their linguistic behaviour to align with

system• May allow modelling of desired input


Patterns of alignment in HCI• How might alignment in HCI pattern?

• If alignment is purely automatic priming:– Alignment would occur whenever a linguistic structure is

encountered

• But in HHI, speakers’ (lexical and syntactic) choices are also influenced by:

– a priori beliefs about addressee knowledge, capability etc

– direct evidence about addressee knowledge, capability etc

• Hence beliefs about the knowledge, capability etc of a system might influence the extent to which speakers align with it.


Relevant factors in HCI alignment• A priori beliefs about social identity of system:

– If systems are treated as social agents just like humans, then alignment should occur just as with humans.

• But which group of humans would count as comparable social agents?

– Limited capability?

– If systems are not treated as social agents just like to humans, then alignment may differ:

• Less alignment if alignment has substantial component related to e.g. politeness


Relevant factors in HCI alignment• Beliefs about system capability:

– Users may assume computers to be less capable (generally and/or specifically linguistically).

• May increase likelihood of aligning, relative to HHI – Possibly different degrees of alignment with different systems

• May increase likelihood of aligning with unusual structure/expression

– Effects of feedback:• A priori beliefs may be updated in light of feedback

• Positive feedback of understanding may lead to comparable alignment as in HHI


Relevant factors in HCI alignment• Beliefs about addressee identity:

– Modality may affect beliefs about addressee identity:

• Use of synthesised speech may emphasise non-humanness of addressee

– Might enhance difference between HCI/HHI

• Use of (canned) speech may de-emphasise non-humanness of addressee

– Might reduce differences between HCI/HHI


Summary• Alignment is potentially highly important in HCI –

but there are many factors that might affect patterns of behaviour.– Specifically, many reasons why alignment in HCI might

differ from alignment in HHI

• One important issue: – extent to which any differences between HCI and HHI are

artifact of communicative situation rather than genuine differences between HCI and HHI

• Involvement of computer in communication


Methodology

Another person or a computer... or whatever

Identical in all conditions

?


Methodology• Picture-description experiments (as in HHI):

– Single object: lexical choices– Actions: syntactic choices

• Manipulate participants’ beliefs about identity of addressee:

– Human (at other end of remote connection)

– Computer (at other end of remote connection)

• In fact, there is no interlocutor:

– Participants always interact with a computer program that produces pre-scripted utterances

– ‘Reverse Wizard-of-Oz’


Methodology• Systematically control addressees’ utterances that

participant encounters:– Actual linguistic behaviour of addressee is always identical

in all conditions

• How do beliefs about addressee affect participants’ likelihood of lexical/syntactic alignment?– Differences in participants’ linguistic behaviour must be

due to differences in beliefs about interlocutor.

– NB: This method is also informative about alignment in computer-mediated HHI.


Outline• Series of experiments investigating:

– Do people align with computers?

– Focus on syntactic and lexical alignment

• Basic effects

• Influences of e.g., modality, a priori beliefs, feedback


Possible patterns• No alignment in HCI:

– Only align with interlocutors that can experience positive affect or have beliefs/knowledge

• Equal alignment in HCI and HHI:– Compatible with cognitive economy accounts

• More alignment in HCI than HHI:– Beliefs about interlocutor’s affect alignment e.g.

knowledge/capability

• (No alignment in HHI– People do not align in CMI)


Syntactic• Interlocutor

– Human vs. Computer

• Two separate experiments: Verb in interlocutor’s description– Same vs. Different in participant’s picture


Syntactic• Interlocutor’s description

– Same PO: The pirate handing the cake to the sailor

– Same DO: The pirate handing the sailor the cake





– Different PO: The pirate giving the cake to the sailor

– Different DO: The pirate giving the sailor the cake





– Different PO: The pirate giving the cake to the sailor

– Different DO: The pirate giving the sailor the cake

• Participant’s picture


Syntactic alignment paradigm

Interlocutor describes

PO or DO

Participant matches



Participant describes

PO or DO?



Interlocutor matches


Results• Align with people and with computers

– No difference in the magnitude of alignment

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Different Verb


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• More alignment with computers than people

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Same Verb


Interim summary• Syntactic alignment occurs in both CMI and HCI

– Tendency to use same syntax as ‘human’ or ‘computer’ interlocutor

• When verb is repeated, more alignment in HCI than CMI– Only difference in in beliefs about interlocutor

– Interlocutor’s behaviour identical


Interim summary• Beliefs about interlocutor can affect strategic

alignment– Overlies ‘basic’ (implicit, non-strategic) alignment

– Syntactic choices not usually open to introspection, hence to strategic influences – only obvious in same-verb condition

• Lexical choices are usually more open to introspection– Hence should be generally more susceptible to strategic

component


Lexical• Interlocutor


• Term used by the interlocutor– Preferred vs. Dispreferred term

• Experimental items pretested– Preferred term used more than 90% (e.g. bench)

– Dispreferred term acceptable (e.g. seat)


Lexical alignment paradigm

Interlocutor describes

Preferred or dispreferred

term

Participant matches



Participant describes

Preferred or dispreferred

term?




computer person

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Interim summary• Lexical alignment occurs in both CMI and HCI

• Greater alignment with computers than people when the availability of such a strategy is obvious

• Beliefs about a system influence the extent that speakers align:– Strongly affects behaviour – >80% use of term that is

strongly dispreferred (<10% use in null context)


Interim summary• Differences in alignment due to differences in a

priori beliefs about interlocutor’s knowledge etc– Interlocutors’ linguistic behaviour identical in all conditions

• Alignment does not reflect beliefs based on feedback from computer’s earlier contributions– Received feedback from computer of understanding of

syntax and lexical choices

• Conservative approach to HCI: A priori assumptions not updated in light of direct evidence– Cf. HHI evidence


Syntactic: Modality• Modality may affect salience of beliefs about

interlocutor identity– Use of synthesised speech may emphasise non-humanness

• Hence promote alignment

– Use of speech may deemphasise non-humanness• Hence reduce alignment


Syntactic: Synthesized Speech• Syntactic alignment: PO/DO

• Interlocutor– Human vs. Computer

• Modality– Text vs. [Synthesized] Speech

• Interlocutor-text / Participant-text

• Interlocutor-text / Participant-speech

• Interlocutor-speech / Participant-text

• Interlocutor-speech / Participant-speech


Results• More alignment with computers than people

• No effect of modality

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Lexical: Canned speech• Same factors as previous

– Spoken version

• Interlocutor’s “voice” pretested– Rated progressively distorted/impoverished versions for

plausibility as a computer or person

• Chosen voice equally plausible as a computer or a person

• Voice gender-matched with participant


Results

computer person

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• Align with people and with computers



Combined analyses

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Interlocutor-text / Participant-text Interlocutor-spoken / Participant-spoken

computer person

• Although in right direction, no significant effect of modality


Interim summary• Increased alignment in HCI is robust effect

– Not reliably influenced by modality, whether synthesised or canned speech

• Beliefs about interlocutor that influence alignment seem to be impervious to relatively superficial and overt manipulations of ‘humanness’– Not a dimension that needs to be worried about in systems

design?


Lexical: Persistence of alignment• Alignment may persist over longer intervening

material if interlocutor believed less capable– More effort to encode and recall interlocutors’ choices in

order to maximise chances of effective communication

• If interlocutor believed to be capable:– Alignment with dispreferred term may occur in short-term

(politeness)

– But not over longer distances


Lexical: Persistence of alignment• Interlocutor


• Distance between interlocutor naming picture and participant subsequently naming it– Near vs. Far

• Near: Immediately preceding turn

• Far: Nine intervening filler turns




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computer near person nearperson farcomputer far


Results• Alignment with people decreases with increased

distance

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Results• Alignment with computers is maintained despite

increased distance

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Interim summary• Need for reciprocity/politeness to other people

diminishes

• Maintain high level of alignment with computers– Conservative approach in HCI: Go to a great deal of effort

to maximise the chances of effective communication


Lexical: Capability• Alignment to computers:

– Robust effect

– Determined by a priori beliefs about addressee knowledge, capability etc

– Not influenced by direct evidence about addressee knowledge, capability etc

• Can we manipulate participant’s beliefs about knowledge, capability etc of interlocutor?


Lexical: Capability of computer• HCI condition only

• Interlocutor– ‘Basic’ computer vs. ‘Advanced’ computer

• Manipulate beliefs about capability– Actual behaviour identical in both conditions

– Only difference: start-up screen for 10 seconds prior to the experiment


Basic computer manipulation


Advanced computer manipulation


Results• Align with basic and advanced computers

• More alignment with basic than advanced computer

basic computer advanced computer

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Pearson et al (CHI-2006)


Interim summary• Beliefs about computer’s capabilities influence

alignment

• Beliefs can be manipulated through simple, superficial, non-functional aspects of system– Not affected by actual behaviour of system (evidence of

understanding)

• Does conservatism wrt updating beliefs on basis of feedback in HCI reflect something specific to HCI?– Are speakers similarly conservative in HHI when

interacting with humans of unknown capability?

– Test group: Non-native speakers


Lexical: Capability of person• CMI conditions only

• Interlocutor– Native person vs. Non-native person

• Manipulate beliefs about capability– Actual behaviour identical in both conditions

– Only difference: participants told they were interacting with native or non-native person


Results• No difference in alignment with non-native than

native people

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Interim summary• Greater alignment with basic than advanced

computer– Determined by a priori beliefs about interlocutor’s

knowledge, capability etc

– Not influenced by direct evidence about interlocutor’s knowledge/capability

• No greater alignment with non-native than native person– Influenced by direct evidence about interlocutor’s

knowledge/capability

• What if we remove direct evidence about person interlocutor’s knowledge/capability?


Lexical: Capability of person(2)• Same factors as previous

• Interlocutor– Native person vs. Non-native person

• No feedback from interlocutor when matching– No direct evidence about interlocutor’s understanding


Feedback


Participant has

described


No feedback


Participant has

described


Results

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• Greater alignment with non-native than native people


Beliefs about mental states• Interlocutors establish a “common ground” of

shared background knowledge Clark & Marshall (1981)

– Each interlocutor works out what they assume the other knows about the situation

• Common ground can be accrued on the basis of:– Linguistic co-presence: What has been said previously

– Community membership: What you can infer on the basis of them belonging to a particular social group


Beliefs about mental states• Greater alignment with computers than people and

with basic than advanced computers– Computers have radically different mental states than us

– Unclear what capabilities computers have, so align to maximise the chances of effective communication

• Greater alignment with non-native than native speakers only in absence of feedback– Non-natives have similar mental states to us

• With feedback: beliefs are up-dated. Based on their contributions, non-natives are capable enough

• Without feedback: cannot assume they are capable, so align to maximise the chances of effective communication


Conclusions• HCI is like HHI in important ways:

– Tendency to align with interlocutor

– Both lexical and syntactic alignment

• But important differences:– Differences in a priori beliefs about human vs computer

interlocutors influences magnitude of alignment

– Where different choices salient, speakers align more with computers than with people

• Strategic component additional to automatic component of alignment


Conclusions• Beliefs in HCI can be manipulated easily

– Superficial non-functional aspects of system

• But beliefs in HCI are not readily updated on basis of behavioural evidence


Interface design implications• Users adapt their behavior to fit the system. This

adaptation reflects beliefs about the system’s capability, and not its actual behaviour

• Improved natural language recognition– To elicit high degrees of alignment, a system should not

claim “humanness”• A computer that tries to act smarter than it actually is is

disliked Wang et al (2005)

– Consistent use of words/syntax by interface will implicitly limit users’ input, reducing burden on recognition systems

– May also have affective implications


Future directions: Align to listener• Alignment/adaptation to one’s interlocutor

increases:– Efficiency executing conversational tasks Clark & Wilkes-

Gibbs (1986)

– Likelihood of achieving higher level goals such as changing beliefs Carenini & Moore (2000)

– Waitress’ tips van Baaren et al (2003)

– Social Psychology: Increased liking; marking as in-group …

• Are people affected by computers aligning with them?

• Do people prefer computers that align with them?


Future directions: Align to listener • Alignment to the user by the system might affect

– Level of alignment by user (can be leveraged to improve recognition accuracy)

– Liking of the system and the other users

– Perceived credibility (expertise and trustworthiness)

– Purchase behaviour

– Task performance

– Web stickiness (amount of time spent on a site)

– Branding effectiveness (multiple visits to a site)


Align to listener: Design• Interlocutor


• Interlocutor’s responses– Align vs. Misalign with participant’s

• Measure characteristics of participant’s responses– Align or misalign with interlocutor?

• Affective measures– Perceptions of the interaction, self, and the interlocutor


Align to listener: Design

• Interlocutor: “boat”




• Participant: “jacket”





• Interlocutor: “jacket” “coat”

align misalign





• Interlocutor: “jacket” “coat”

• Participant: align and say “boat”?

align misalign

alignment in human-human and human-computer interactions

Documents

addressee likely

speakers beliefs

addressees state of

choice of lexical terms

individual speakers

assumed knowledge

linguistic choices semantic

lexicalsyntactic alignment