Negotiative dialogue some definitions and ideas

Negotiation vs. acceptance Clark’s ladder: –1. A attends to B’s utterance –2. A percieves B’s utterance –3. A understands B’s utterance (grounding) –4. A accepts or rejects B’s utterance Sidner and others sees negotiative dialogue as proposals and acceptance/rejections of proposals –this means that all dialogue is negotiative –all assertions (and questions, instructions etc.) are proposals But some dialogues are negotiative in another sense, by explicitly containing discussions about different solutions to a problem, and finally deciding on one –Negotiation is not Clark’s level 4

Two senses of “negotiation” Negotiation in Sidner’s sense –A: I want to go to Paris [propose] –B(1): OK [accept] –B(2): Sorry, there are no flights to Paris [reject] Negotiation in our sense –U: flights to paris on september 13 please [answer] –S: there is one flight at 07:45 and one at 12:00 [propose] –U: what airline is the 12:00 one [ask] –S: the 12:00 flight is an SAS flight [answer] –U: I’ll take the 12:00 flight please [accept]

Optimistic approach to acceptance DPs assume their utterances are accepted (and integrated into SHARED ) –If A asks a question with content Q, A will put Q topmost on SHARED.QUD If addresse indicates rejection, backtrack –using the PRIVATE.TMP field No need to indicate acceptance explicitly; it is assumed The alternative is a pessimistic approach –If A asks a question with content Q, A will wait for an acceptance (implicit or explicit) before putting Q on top of QUD

Negotiativity Negotiation is a type of problem-solving (cf. Di Eugenio et. al., Coconut) Negotiation: DPs discuss several alternative solutions before choosing one of them Negotiation does not imply conflicting goals –perhaps not 100% correspondence to everyday use of the word “negotiation”, but useful to keep collaborativity as a separate dimension from negotiation Both AOD and IOD can be negotiative –in a flight information service, the user does not become obliged to fly anywhere; so it’s IOD –but several different flights may be discussed

Negotiation tasks Some factors influencing negotiation –distribution of information between DPs –whether DPs must commit jointly (e.g. Coconut) or one DP can make the comittment (e.g. flight booking) We’re initially trying to model negotiation in flight booking –sample dialouge U: flights to paris on september 13 please S: there is one flight at 07:45 and one at 12:00 U: what airline is the 12:00 one S: the 12:00 flight is an SAS flight U: I’ll take the 12:00 flight please –Sys provides alternatives, User makes the choice –Sys knows timetable, User knows when he wants to travel etc.

Degrees of negotiativity non-negotiative dialogue: only one alternative is discussed semi-negotiative dialogue: a new alternative can be introduced by altering parameters of the previous alternative, but previous alternatives are not retained negotiative dialogue: several alternatives can be introduced, and old alternatives are retained and can be returned to

Semi-negotiative dialogue Does not require keeping track of several alternatives Answers must be revisable; this can be done using reraising of answered questions Correction of optimistic assumption of acceptance not necessarliy distinguished from revision Example: Swedish SJ system (Philips): ”Do you want an earlier or later train?”

Issues Under Negotiation i negotiative dialogue IUN is a question e.g. what flight to take In an activity, some questions are marked as negotiable issues; other questions are assumed to be non- negotiable Needs a new IS field: SHARED.IUN of type assocset(question,set(answer))

Alternatives in negotiation Alternatives are alternate answers to an IUN a proposal is the introduction of a new possible answer to IUN An IUN is resolved when an answer to it is given, i.e. when an alternative is accepted Alternatives and information about them is optimistically assumed to be accepted Alternatives are needed whenever database search can return more than one result

General and specific information General information concerns all alternatives, and is collected in an initial information- seeking dialogue (e.g. flights to paris) –e.g.  x.dest(x,Paris) Specific information concerns specific alternatives (e.g. flight f345 leaves at 10:45) Specific info usually results from a database search whose input is general info; does this motivate separate fields in IS?

Example IUN is x.sel_flight(x) (“which is the chosen flight”?) A: flight to paris, december 13 –answer(  x.dest(x,paris)) etc.; B: OK, there’s one flight leaving at 07:45 and one at 12:00 –propose(f1), propose(f2), –answer(dep_time(f1,07:45)), answer(dep_time(f2,12:00)) A: I’ll take the 07:45 one –answer(sel_flight(X), dep_time(X, 07:45)), –after contextual interpretation: answer(sel_flight(f1))

PRIVATE = PLAN = AGENDA = { findout(? x.sel_flight(x)) } SHARED = findout((? x. ccn(x)) book_ticket COM = dep_time(f1,0745), dep_time(f2,1200)  x.dest(x, paris),... QUD = <> LM = {propose(f1), propose(f2), answer(dep_time(f1,07:40),...} BEL = { flight(f1), dep_time(f1,0745),... } TMP = (same structure as SHARED) IUN = B: OK, there’s one flight leaving at 07:45 and one at 12:00

Interpretation of NPs Interpretation of ”the 7:45 one” uses unification and coercion –all answer-contents which match propositions in SHARED.COM is unifed with this info; e.g. dep_time(X,07:45) is unified with dep_time(f1,07:45) –the rest is added, e.g. sel_flight(X) with X=f1

Database search Consulting DB with a set of (general) facts and a question (e.g. X^flight(X)) gives a list of alternative answers to the question AND info related to each of these alternatives Example –FLIGHTDEP_TIMECOMPANY –f107:45KLM –f212:00SAS After doing the inital DB search, store results in PRIVATE.BEL, give some information about each alternative, e.g. flight departure time

Plans some info must be obtained from user, and some is found in DB; how flexible is this division? a simple solution –departure date, destination, origin and class is obtained from user –(exact) departure times, company etc is always found in DB –departure times are always adressed when giving proposals; other info can be requested by user flight booking –findout(X^dest_city(_,X)),... –consultDB –propose –adress(X^dep_time(_,X)) –findout(X^sel_flight(X)) a better solution: implicit negotiation of dialogue strategy (Lewin)

Revising general information Problem when general information is revised –solution: see it as defaults; if it is altered, turn it into specific info for all current alternatives which do not contradict the default