Scope Ambiguity
Scope and Anaphora
antecedent vs. postcedent
anaphor vs. cataphor
Predicate logic is suited to capture natural language meaning
allow recursion = recursivity
two sources of recursion
- coordination: john likes cats, dogs, beer
- embedding: John said that Mary knws that Bill thinks that Jane claims that
linear order: negative polarity item
graph TD
DS -.Transformation.-> SS
SS -.send off.-> PF
SS -.send off.-> LF
PF -.acoustic representation.-> SS
LF -.semantic interpretation.-> SS
Transformation:
- Jane laughed at Bill
- Bill was laughed at by Jane
CALLOUT: annotation, connotation and denotation
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annotation
- a critical or explanatory commentary or analysis
- a comment added to a text
- the process of writing such comment or commentary
- (computing) metadata added to a document or program
- (genetics) information relating to the genetic structure of sequences of bases
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connotation: intension.
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A meaning of a word or phrase that is suggested or implied, as opposed to a denotation, or literal meaning. A characteristic of words or phrases, or of the contexts that words and phrases are used in.
The connotations of the phrase "you are a dog" are that you are physically unattractive or morally reprehensible, not that you are a canine.
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A technical term in logic used by J. S. Mill and later logicians to refer to the attribute or aggregate of attributes connoted by a term, and contrasted with denotation .
The two expressions "the morning star" and "the evening star" have different connotations but the same denotation (i.e. the planet Venus).
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denotation
- its explicit or direct meaning, as distinguished from the ideas or meanings associated with it or suggested by it. Simply put, a word’s denotation is what that word means or directly represents.
Solution for scope ambiguity
Quantifier-raising - NC RM - syntactic structure comes before the semantic structure - The movement we make in SS to remove ambiguity in DS is called quantifier-raising. - take the quantifier to the higher position to show the scope
Quantifier-in - Montague grammar - The derivational illustration is called quantifier-in. - each predicate take an argument once a time
Quantifier storage - Cooper storage - semantic ambiguity not represented in syntactic structure - semantic representation in which scope ambiguities are obtained without special syntactic rules
Quantifier-in
interrogative: asking a question
which scopes over every.
Scope ambiguity
e.g. some boy did not laugh.
some boy kissed no girl.
\exist x (Boy(x) and ~\exist y (Girl(y) and Kiss(x, y)))
~\exist y (Girl(y) and \exist x (Boy(x) and Kiss(x, y))): there was no girl kissed by a boy
every boy kissed no girl.
Deictic
No boy said he was hungry.
No boy was present. He was outside instead.: “he” is trying to refer to ”no boy” but outside the scope.
pronoun \(\sub\) anaphora
Discourse Anaphora
e.g.
every: scopes over “Every student was present”
every: an indefinite quantifier. “she”’s antecedent is not clear
“she” is hardly bound by the antecedent. “she” is free * ungrammatical: 不合语法的, syntactic
infelicitous: 不合适的, semantic, fit the context
:material-circle-edit-outline: 约 1349 个字 :fontawesome-solid-code: 15 行代码 :material-clock-time-two-outline: 预计阅读时间 5 分钟
- sentence pronoun: within the same clause
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discourse pronoun: in separate clauses
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sentence quantifier:
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discourse quantifier:
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coreference individual constants
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binding individual variables
So we may conclude the following rules for e-type anaphora. BUT this part has NOT been verified with any authority. Do NOT take them as given truths during exams.
- F: universal quantifier + singular pronoun
- T: universal quantifier + plural pronoun
- F: negated quantifier + singular pronoun
- T: negated quantifier + plural pronoun, semantically plural but grammatically singular
- T: existential quantifier + singular pronoun
e.g. No boy thinks that he has a chance.
A particular boy said he wanted to kiss every girl. He then did it.
Donkey anaphora
if a farmer owns a donkey, he beats it.
* \exist x (Fx and \exist y (Dy and O(x, y))) -> B(x, y)
\forall x \forall y (Fx and Dy and O(x, y) -> B(x, y))
= every farmer who owns a donkey beats it.
❗❗❗
A donkey sentence is such that an expected existential is interpreted as universal taking wide scope.
donkey pronoun can be: it, him, they (can also be plural forms)
“a”: generic indefinite
[Every farmer [who owns a donkey] beats it.]
universal wide scope: it scopes more over the relative clause
The problem - Existential with narrow scope - interpreted as universal with wide scope - in conditional clauses - in restriction of every
Conclusion - the machinery of predicate logic is broken - cannot capture meaning of natural language
If a student tries, she passes the exam.
interpretation
Solutions for donkey anaphora:
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E-type anaphora
- Gareth Evans, 1970s, philosopher, university of Oxford, logic, philosophy of mind
- pronoun outside the scope of their binder
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initial examples
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If a student likes Copenhagen, she is happy.
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every student who reads a semantic paper likes it.
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DRT (Dynamic binding theory)
- discourse anaphora and donkey pronouns
- intermediate level
- Irene Heim (1982) and Hans Kamp (1981)
- Discourse Representation Theory (DRT)
- embedding conditions
- language of boxes
- boxes constantly updated
- embedded boxes in accessible
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Unselective binding example of the subject is ‘unselectively bound’ by a special ‘generic operator.
Reference: Unselective Binding
Chapter 6 in short: Discourse/Donkey Anaphora
(加粗的是Donkey anaphora和E-type anaphora的区别)
Discourse: basic unit of interpretation
- Dynamic theory of meaning: look beyond the meaning of individual sentences and determine the way they are pieced together to make discourse
- discourse anaphora: anaphora in sequence of sentences (instead of single sentence)
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Donkey sentence: is such that an expected existential is interpreted as universal taking wide scope. / sentences that contain a pronoun with clear meaning but whose syntactical role in the sentence poses challenges to grammarians (wikipedia)
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donkey anaphora = donkey pronoun: it, him, they (can also be plural forms)
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Analysis of donkey anaphora: Montague grammar
e.g.
Anaphoric relations in sentence and discourse - E-type anaphora: pronoun outside the scope of binder, not bound, content of pronoun reconstructed, reconstruction based on context - in separate sentences
```
A student came in. *She*(the student came in) had a question about the exam.
```
- in the same sentence but outside the scope
```
If a student likes Copenhagen, *she*(for every case we examine, the student in question who likes Copenhagen) is happy.
```
- problem of compound: antecedent must appear as a noun?
```
Bill owns a cat. Max takes care of it.
Bill is a cat-owner. # Max takes care of it.
```
- unselective binding + Discourse Representation Theory (DRT)
- embedded conditions
- language of boxes, boxes constantly updated
- Accessibility: the antecedent to be in a box ‘as high as’(same box or left box) or ‘higher than’ the discourse referent for the pronoun
- ⇒ binds all left variables. unselective quantification over all the variables. unselective binding
- dynamic binding
- TODO
Anaphora resolution - TODO