-
Lexical semantics
-
1st attempt
-
davidson's problem
- entailments not natural
-
davidson' proposal/ Event semantics
-
for event verb
- introduce e
- predicate(e, _ ,_ ) \and adjuncts
-
model structure
- introduce event space
- (Individual universal, event universal, interpretation function)
- variable assignment function
- for different domains
-
added values
- natural representation of adjuncts
- natural and uniform interpretation event verbs and nomial event predicates
- uniform treatment of NPs and infinitive constructions as verb complements
- bill saw an elephant
- bill saw an accident
- bill saw the children play
- intuitive semantic constructions for adjuncts
- it rains at midnight
- at midnight
- adjuncts modify event predicate
- uniform treatment of noun modifiers
- the murder in the park
- the fountain in the park
- the plausible integration of tense
-
tense
- classical tense logic
- representations
- with tense operators
- p
- Pwalk(john)
- f
- Fwalk(john)
- tense logical model structure
- M= <U, T, <, V>
- U \union T= \empty
- < a linear ordering on T
- V value assignment function
- interpretation
- temporal event structure
- M = (U, E, T, < , t_u, tl, V)
- U, E, T mutually disjoint
- < linear ordering on T
- t_u \in T
- utterance time
- tl
- function from E to interval of T
- V interpretation function
- order of events
- precedence of events
- e < e'
- for all t \in tl(e), t' in \tl(e')
- t < t'
- overlapping events
- e \circle e'
- iff
- tl(e) \conjunt tl(e') \neq \empty
- stative vs non-staive
- stative
- know
- believe
- have
- desire
- love
- non-stative
- kick
- run
- walk
- build a house
- Summary
- with extra argument e!
-
event semantics
-
stative vs event
-
linguistic distinction
- progressive form
- john is running
- john is reciting a poem
- john is knowing the answer
- simplest present
- mary runs
- has the habit of running
- john recites peoms
- has the habit of reciting poems
- john knows the answer
- manner adverbials
- John ran carefully
- John carefully recited the poem
- John carefully knew the answer
-
conclusion
- verb semantics using events
- natural
- however
- not all verbs
- event-expressing verbs do not form a homogeneous semantic class
-
differences
-
different distribution of duration adverbials
- e.g.
- john painted a picture in an hour
- john walked in an hour
- it rained in an hour
- john walked for an hour
- it rained for hour
- john painted a picture for an hour
- it took john an hour to paint a picture
- it took john an hour to walk
-
different inferential properties
- john walked from 8am to 11 am
- john walked from 9 to 10 am
- it rained from 8 am to 11 am
- it rained from 9 to 10 am
- john painted a picture from 8am to 11 am
- not!
- john painted a picture from 9 to 10 am
- john is working in Saarbrucken
- John has worked in Saarbrucken
- it is raining in Saarbrucken
- it has rained in Saarbrucken
- john is painting a picture
- not
- john has painted a picture
- john stopped walking
- john walked
- it stopped raining
- it rained
- john stopped painting a picture
- not
- john painted a picture
-
aspectual verb classes(relation to time)
-
states
- know
- believe
- own
- love
- resemble
-
eventualities
- processes/activities
- run
- walk
- swim
- work
- sleep
- rain
- (Proper) Events
- e.g.
- paint?
- still not homogeneous!!!
- accomplishments
- (succeed in doing somehing)
- achievements
-
vendler's classification
- duration?
- bound?
- Problem remained
- what is the essential ontological difference
- compositional treatment?
-
NOUNs
-
plural NPs
- collective predicates
- Bill and Mary met
- not
- Bill met
- The students gathered, John is a student
- not
- John gathered
- e.g.
- meet
- gather
- unite
- agree
- distributive predicates
- Bill and Mary worked
- Bill worked
- The students worked, John is a student
- John worked
- modeling
- idea
- structured universe
- entities
- atomic
- sum/group
- plural
- group
- lattice
- partial order
- reflective
- transitive
- antisymmetric
- closed under
- join
- meet
- differences
- collecitve
- V_M(F) \in U\A
- distributive
- distributivity
- closure under summation
- mixed
- not distributive
- but closed under summation
- e.g.
- carry a piano
- solve the exercise
- language
- summation operator
- +
- At
- atom
- (proper) individual part
- number specific predicates
- interpretation
- +
- <|
- individual constants
- atoms
- sums
- number-specific predicate
-
mass nouns(3)
- vs plurals
- similarities
- closed under summation
- combine with cardinalities
- 5 students
- 5 liters of water
- share grammatical patterns
- differences
- divisive
- denotations cannot be reduced to atomic individuals
- modeling
- another sort of entities
- portions of matter
- non-atomic and dense join semi-lattice
- language
- add
- +_m
- <|_m
- materialization function
- m (type <e, e>)
- object-matter relation
- h
- map atomic and pluralic individuals to matter
- homomorphism
-
event semantics in analogy to plural semantics
-
idea
- sub-event relation
- join semi-lattice
- (U, <E, <=_e>, <, e_u, V)
- <
- asymmetric relation
- e_u
- utterance event
- <E, <=_e>
- join semi-lattice
- V
- interpretation function
-
application
- scripts
-
process event vs proper events
- process
- similar to mass
- cumulative
- divisive
- M = (!U, !i", !M, !m", h, !Ei, !ei" , !Em, !em", he, <, eu, V)
- progressive tense
- thematic role
-
compositional semantics
-
first order logic(recap)
- describe properties and relations of individuals
-
individuals
- CON
- VAR
- terms?
- quantification is also on individuals
-
limitation
-
modification
- good student
- sentence embedding verbs
- higher order quantification
- Doesn't support Compositional semantics
-
Summary
- so the limitation is due the central place of INDIVIDUALS
- we want to also talk about properties of relations
-
aim
- can compute meaning from small pieces
-
Type theory
-
richer inventory
- higher order relation
-
teminology
-
Types
- basic types
- e
- entities
- t
- truth-values
- complex types
- indicates how many arguments, what types the arguments must have
-
vocabulary
- constants
- variables
- logical symbols
-
syntax
-
well formed expressions for t
- CON and VAR
- <\theta, \tau> + \theta
- with logic connectives
- with quantifiers
- equation
-
semantics
-
domain of possible denotations
- D_e = U
- D_t={0,1}
- characteristic functions
-
model structure
- U
- individuals
- V
- interpretations function for CON
- variable assignment
-
meaning postulates
- to get intended entailment relations
- restrictions on models
- constrain the possible meaning of certain words
- eg
- adjectives
- intersective
- subsective
- privative
-
construction
- 1st version
- apply verb to noun
- problems
- quantifiers on NP
- complex NP
- 2nd version
- motivation
- use lambda abstraction
- apply NP on VP
- lambda operation
- we + lambda
- scope
- smallest WE
- \lambda x.
- widest possible scope
- beta reduction
- variable capturing
- due to
- name
- scope
- construction rules
- N
- NP
- DET
- VP
- TV
- IV
-
type for expressions
-
<e,t>
- nouns
- student
- adjectives
- red
- a meaning of type <e,t>
- property
- set
- unary predicate
- intransitive verbs
- verb phrases
- hate Mary
- relative clauses
-
e
- proper name
- definite description
- the professor
-
<<e,t>, t>
- quantification expression
- no one
- every one
-
<<e,t>,<<e,t>,t>>
- determiner
-
lambda calculus
-
predicate
- the number of arguments is not specified
- type of arguments is not specified
-
benefits
- a way to express complex properties/ sets
- e.g.
- lazy professor
- \lambdax . lazy(x) \and professor(x)
- type shifting
-
how to create lambda formula from predicate
- first do lambda abstraction according to the number of place
- Then choose place to put the place holder for the direct object
-
scope ambiguity
-
reason
- mismatch between syntactic and semantic structure
-
cooper storage
- introduction
- expression are assigned ordered pairs
- content
- quantifier store
- quantifiers
- either apply in situ
- or move to store for later application
- sentence node
- retrieval
- semantic representation
- if store is empty
- storing a quantifier
- move it upwards
-
Discourse Semantics
-
DRT
-
difference with logic
-
no quantifiers symbol
- depends on the context
-
accessblity
- conditions can use discourse referents
- why important
- a man sleeps
- \exist x (M(x) \and S(x))
- not every man doesn't sleep
- \not \any (M(x) \implies \not S(x))
- In DRT
- not fully equivalent
- +"he snores"
- 1=> perfect
- 2=> can not refer to x
- can not look downwards
- another example
- "a man doesn't sleep, he is awake"
-
not only truth condition,
- model embedding
-
but also anaphoric potential
- DRS construction
-
semantic representational theory
- while logic concerns about truth condition
-
truth condition
- K is true in M iff there is a verifying embedding f of K in M such that Dom(f) = U_K
- construction rules
- translation rules
-
DRSs
- simple DRSs
-
conditional DRSs
- motivation
- donkey sentence
- K_1 => K_2
- K_1
- antecedent DRS
- K_2
- consequent DRS
-
non-compositional
- needs structural information
-
presuppostions
- requirements that the context must satisfy for the utterance to be interpretable
- usually to top level
-
sometimes blocked
- the king has a son
- the king's son is bald
-
if the king has a son, the king's son is bald
- there is a king
- survive
- the king has a son
- cancelled
-
some triggers
- definite noun phrases
- quantifiers
-
factive verbs
- regret, realize
- implicative verbs
- aspect
- appostions, non-restrictive relative clauses
- it-clefts
- sentence particles
- presupposition projection
-
presupposition filtering
- block projection
- presupposition cancellation
-
tree levels of meaning
- assertions
- presuppostions
-
conversational implicatures
- cooperative principle
-
four maxims of conversation
- maxim of quality
- don't say what you believe to be false
- don't say that for which you lack evidence
- maxim of quantity
- maxim of relevance
- maxim of manner
-
presuppositions in DRT
-
overview
- anaphora with semantic content
-
anaphora binding
- filtering
-
not bound
- accommodated
-
idea
-
anaphora
- the cancellor decides
- there is a chancellor, (s)he decides
-
\alpha DRSs
- definite noun phrases
- \alpha DRSs
- pronouns
- proper names
- standard
- \alpha
- both ok
- possessives
- resolve \alpha DRSs
- bind
- accormodate
- usually happens on the top level
-
preference
- binding > accommodation
- binding: closest possible
- accommodation: highest possible
-
constraints
- free variable
- further constraints
-
overview
-
truth-conditional semantics
- to know the meaning
- to know the world when the sentence is true
- sentence meaning = truth-conditions
-
central concepts
- reference and denotation
- Truth and truth conditions
- Entailment and inference
-
compositional semantics
-
semantic construction
-
interpretation of adjectives
- john is a blond piano player
- john is blond
- john is a poor piano player
- john is poor
-
quantifier scope
-
quantifier
- related to quantity
- every
- a lot of
- many
- ...
- Summary
- type of determiner
- generalized quantifiers
-
discourse semantics
- anaphora and ellipsis
- DRT
- presuppositions
- tense and temporal structure
-
lexical semantics
- event semantics
- thematic roles
- plurals, mass nouns, collective predicates
-
formal foundations
-
predicate logic
-
Vocab
-
Non-logical expression
- individual constants
- CON
- Relation constants
-
infinite set of individual variables
- VAR
- logical connectives
- Brackets
-
Syntax
-
Terms
- VAR
- CON
-
atomic formulas
- R
- t1=t2
-
well-formed formulas
- all atomic
- wff + logical connectives
- wff + quantifier
-
free and bound variables
- all related to quantifier
- sentence
- is a formula without free variables
-
semantics
-
interpreted with model structure and variable assignment
- why?
- model structure is something models the world
- we care about the world when the sentence is true
- it means we care about the model structure when the sentence is true
-
model structure
- U_M
- universe
- non empty
- can be considered as where the individuals live
- V_M
- interpretation function
- for constants
- V_M(P) \subseteq U_M^n
- for n-place predicate symbol
- V_M(C) \in U_M
-
interpretation
- Terms
- [[a]]^{M,g}
- V_M(a)
- constant
- g(a)
- variable
- Formulas
- see the slides
- atomic
- with logic connectives
- with quantifiers
- variable assignment
- the idea is we only care about small part the function
- then just record the changed thing
-
truth
- true
- formula is true in a model structure M iff interpretation is true for all variable assignment
- valid
- true in all model structures
- satisfiable
- true in at least one model structure
- entails
-
Generalized quantifiers
-
definition
- a set of properties
- a set of sets
- relation between set and set
-
motivation
- what formal properties do quantifiers hold
- what natural subclasses can be distinguished
- which subclasses actually represent meanings of noun phrases
-
phenomenon
-
negative polarity items
- noboday saw anthing
- somebody saw anything
-
there sentence
- there is John in the garden
-
coordination
- no man and few women walked
- a man and few women walked
- how
- and
- but
- Subtopic 3
-
monotonicity
- upward
- downward
-
language universals
-
monotonicity constraint
- simple noun phrase of any natural language express monotone quantifiers or conjunctions of monotone quantifiers
-
simple noun phrase
- proper names or noun phrases
-
negation of quantifiers
- external negation
- internal negation
-
monotonicity
-
if upward
- then both negations are upward
- vice versa
- dual
-
example
- Topic
-
determiners
-
binary quantifiers
- monotonicity according to verbs
- and according to nouns
-
interpretation
- can be considered as the relation between two sets
-
persistence (according to nouns)
- upward
-
antipersistence
- downward
-
conservativity
- Q(A, B) <=> Q(A, A \and B)
-
test
- all students work
- all students are students that work
-
lives on
- Q lives on X
- for all Y, Y \in Q iff X \conjuct Y \in Q
-
only
- not a determiner?
-
Summary
-
related to monotonicity
- first argument
- second argument