COMPUTATIONAL APPROACHES TO REFERENCE

COMPUTATIONAL APPROACHES TO REFERENCE JEANETTE K. GUNDEL AND MASSIMO POESIO

LECTURE 1: INTRODUCTION SOME BASIC TERMINOLOGY • Reference – process whereby speakers (language producers) use language to refer or pick out some individual or object. • Referring expression – an expression used to perform an act of referring, associated with an entity in the discourse model. • Referent – the entity in the speaker/hearer’s mental model that the referring expression is associated with. • Coreference – When two or more referring expressions share the same referent. • Anaphoric reference – reference to an entity previously introduced/evoked into the discourse. • Antecedent – the phrase that first introduces the entity and thereby licenses the anaphoric reference. • Discourse model - a model of entities introduced into a discourse.

Nominal expressions, including full definite NPs and pronouns, don’t always have a linguistic antecedent. The N (1) s: hello can I help you u: yeah I want t- I want to determine the maximum number of boxcars of oranges that I can get to Bath by 7 a.m. tomorrow morning so hm so I guess all the boxcars will have to go through oran- through Corning because that's where the orange juice factory is [Trains Corpus. Heeman & Allen 1995] (2) If one takes a step back and looks at the rest of this week’s music-group news, the situation looks bad for ugly, unpredictable rock ‘n’ roll: one of the most popular American rock bands of the 90’s, the Smashing Pumpkins, announced that it would break up after its current tour, while Noel Gallagher of the biggest British rock band of the 90’s, Oasis, walked out on the group mid-tour. [Neil Strauss, Teeney-Boppers Shatter a Record. New York Times 5.24.2000]

Dem N (3) A restudy of pareiasaurs reveals that these primitive reptiles are the nearest relatives of turtles. [M.S.Y. Lee, The origin of the Turtle Body Plan. Science, 1993, p. 1649]. (4) (Speaker holding up a tie) Do you think thistie will go with my blue suit.

Demonstrative Pronoun (5) (Dentist to patient) Did that hurt? [from Jackendoff 2002] (6) “We believe her, the court does not, and that resolves the matter,” [NY Times, 5/24/ 00] (7) Anyway , going back from the kitchen then is a little hallway leading to a window, and across from the kitchen is a big walk-through closet. On the other side of that is another little hallway leading to a window…[personal letter, from Gundel et al 1993]

Personal Pronoun (8) (Speaker sees addressee looking at a picture)She looks just like her mother, doesn’t she? [Gundel 1980] (9) What do you think he would do if Taylor’s baby died? Do you think he’d just go on with his life like nothing mattered? Like it didn’t even happen. [“The Bold and the Beautiful”, Jan. 30, 2001, CBS] (10) We gave each of the boys a shirt, but they didn’t fit. [Webber 1978] (cf.. They make such nice gifts)

What do hearers know that enables them to understand a speaker’s intended referent? • What kinds of facts do we need to account for? Descriptive content For some nominal expressions, understanding the descriptive content, what kind of thing it is, is enough.

(11) Central to the case was a Lewinsky-Tripp conversation that Mrs. Tripp taped on Dec. 22, 1997. This was the last talk between the two women that Mrs. Tripp recorded, and it occurred, prosecutors said, just after herlawyer had informed her that secret tape-recording was illegal in Maryland. [Don van Natta, Maryland is dropping wiretap case against Tripp. New York Times 5.24.2000] (cf. also `the largest number of boxcars that I can get to Bath..’ in (1) Syntactic Constraints on Co-reference ‘her’ in (11) can’t be coreferential with `her lawyer`

In most cases (especially pronouns, demonstrative, and definite article phrases) descriptive content grossly underdetermines the intended interpretation. • Cognitive Status. Does a representation already exist in memory and, if so, how salient is it? (11) Central to the case was a Lewinsky-Tripp conversation that Mrs. Tripp taped on Dec. 22, 1997. This was the last talk between the two women that Mrs. Tripp recorded, and it occurred, prosecutors said, just after her lawyer… `this` can refer to the conversation, Dec. 22, 1997, or the situation described by the previous sentence ‘the two women’ can refer to Lewinsky and Tripp or some other two women that the addressee can uniquely identify ‘it’ can only refer to the taped conversation

Replacing one pronoun or determiner with another can yield a different interpretation (descriptive content remains the same) (7) Anyway , going back from the kitchen then is a little hallway leading to a window, and across from the kitchen is a big walk-through closet. On the other side of that is another little hallway (7’)Anyway , going back from the kitchen then is a little hallway leading to a window, and across from the kitchen is a big walk-through closet. On the other side of it is another little hallway leading to a window

(3) A restudy of pareiasaurs reveals that these primitive reptiles are the nearest relatives of turtles. (3’) A restudy of pareiasaurs reveals that the primitive reptiles are the nearest relatives of turtles.

 some determiners and pronouns constrain possible interpretations by conventionally signaling different cognitive statuses (memory and attention states) assumed of the mind of the addressee with regard to the intended referent. The Givenness Hierarchy (GH) (Gundel, Hedberg and Zacharski 1993) in uniquely typefocus > activated > familiar > identifiable> referential > identifiable it this, that, this N that N the N indefinite this N a N

Type identifiable - identify what kind of thing this is. • Referential- associate a unique representation by the time the sentence is processed • Uniquely identifiable - associate a unique representation by the time the nominal is processed • Familiar - associate a representation already in memory • Activated - associate a representation from working memory • In focus - associate a representation that attention is currently focused on. It doesn’t matter how something acquires a particular status , e.g. whether or not it was introduced linguistically

I couldn’t sleep last night a. A dog next door kept me awake • This dog next doorkept me awake • The dog next doorkept me awake. d. That dog next doorkept me awake. e. This dog/that/this kept me awake. f. It kept me awake. Some Predictions of the GH Framework • Definite descriptions, full and pronominal demonstrative phrases, and personal pronouns all require the referent to be at least uniquely identifiable, either directly (the) or by implication (that dog, this, it, etc.)

A cognitive status can be appropriately coded by more than one form, since lower statuses are entailed by higher ones (e.g. `the` is underspecified for familiarity) • (13) These incredibly small magnetic bubbles are the vanguard of a new generation of ultradense memory storage systems. These systems are extremely rugged… [G. Graff. Better bubbles. Popular Science 232(2):68 (1988)] (13’) These incredibly small magnetic bubbles are the vanguard of a new generation of ultradense memory storage systems. The systems are extremely rugged Those systems are extremely rugged. These are extremely rugged. Ultradense memory storage systems are extremely rugged

these primitive reptiles in (3) refers to pareiasaurs as they are the only activated plural entity at the point when the phrase is encountered. Replacing these with the would only restrict the reference to entities the addressee might have in memory or could otherwise uniquely identify. (3) A restudy of pareiasaurs reveals that these primitive reptiles are the nearest relatives of turtles. (3’) A restudy of pareiasaurs reveals that the primitive reptiles are the nearest relatives of turtles.

(11) Central to the case was a Lewinsky-Tripp conversation that Mrs. Tripp taped on Dec. 22, 1997. This was the last talk between the two women that Mrs. Tripp recorded, and it…. it in (11) must refer to the taped conversation between Tripp and Lewinsky, as there are no other singular, neuter entities in focus.

(11) Central to the case was a Lewinsky-Tripp conversation that Mrs. Tripp taped on Dec. 22, 1997. This was the last talk between the two women that Mrs. Tripp recorded, and it…. ‘this’ in (11) can refer to the conversation,the date, or the entity derivable from the state of affairs described in the previous sentence, i.e. the fact that the taped conversation between Tripp and Levinsky is central to the case .

Relevance, Processing Effort and The Grammar-Pragmatics Interface • The restriction that the requires the addressee to associate a unique representation, makes Lewinsky and Tripp possible referents for the two women in (11) , since a representation of these two women is already in memory. But descriptive content and cognitive status don’t uniquely determine the intended interpretation here.

Methodological Issues How do we determine cognitive status? How do we know what status a referent has?

that in (7) restricts possible referents to the activated kitchen, hallway, window and walk-through closet. But cognitive status alone doesn’t explain why the closet is the most natural interpretation. (7) Anyway , going back from the kitchen then is a little hallway leading to a window, and across from the kitchen is a big walk-through closet. On the other side of thatis another little hallway leading to a window

Indefinite NPs usually introduce a non-familiar referent. But not always. (14) K1: It was really interesting, from Minneapolis to Mankato I was sitting next to a black woman. I don’t know how old she was, probably my age or a couple years older, from Kansas City, who was going to the U, majoring in Spanish. She said that her Spanish teacher this quarter was Japanese. N1: Is that right? Japanese. Oh wow. K2: Yeah. N2: And she was teaching it to a black woman – or he, or whatever. [Frederickson tapes, Gundel and Mulkern 1998]]

Food Service portion is a requirement for residency. You were issued an Owen Cafeteria ID card which you will use to charge food in the Owen cafeteria. The food serviceportion of the daily charge may be spent whenever the operation is open for business. To calculate how much you may charge in the cafeteria, simply multiply the number of days of your stay by $8 (here for thirty days or less) or $2.40 (here for 30 days or more); (4 day stay @ $8 =$32). This $32 may be used at anytime during the entire four day stay or (it) may be used all at once. In the event you charge more than the $32, you will be billed the additional amount.

COMPUTATIONAL APPROACHES TO REFERENCE