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Hot and Odd Topics in Semantics
Static Semantic Properties
Katharina Stein
04.05.2018 Static Semantic Properties 1
Outline
• Classes of semantic properties of entities
• Actual researches
04.05.2018 Static Semantic Properties 2
Semantic Properties of Entities
• Various ways to classify the properties of entities
• Eight (possible) classes of properties of entities:• Specificity• Animacy• Sex and gender• Kinship• Social status• Physical properties• Function• Boundedness
04.05.2018 Static Semantic Properties 3
Semantic Properties of Entities
Specificity
• refers to the uniqueness or individuation of an entity in a mentally projected world
• I‘m looking for a man who speaks French.
• Two readings:
• Specific: I‘m looking for a particular man who speaks French.
• Nonspecific: I‘m looking for any man who speaks French.
04.05.2018 Static Semantic Properties 4
Semantic Properties of Entities
Specificity
• refers to the uniqueness or individuation of an entity in a mentally projected world
• I‘m looking for a man who speaks French.
• Two readings:
• Specific: I‘m looking for a particular man who speaks French.
→ And I found him.
• Nonspecific: I‘m looking for any man who speaks French.
→ And I found one.
04.05.2018 Static Semantic Properties 5
Semantic Properties of Entities
Specificity
• Often formal differentiation between specific and nonspecific entities
Spanish:
• Differentiation by the mood of the verb
• Specific: Busco a un hombre que habla francés → indicative mood
• Nonspecific : Busco a un hombre que hable francés → subjunctive mood
• specificity implies uniquely determined reference -> actual mood
04.05.2018 Static Semantic Properties 6
Semantic Properties of Entities
Specificity: Factivity and Negation
• specificity is related to actual moods
• Expectation: specificity in factive context and nonspecificity in negative context
• I regretted reading a book. vs I didn‘t read a book.
04.05.2018 Static Semantic Properties 7
Semantic Properties of Entities
Specificity
• A few languages explicitly differentiate specifics from nonspecifics
Bemba:
• Differentiation per prefixication:
• VCV prefixes indicate specificity
• CV prefixes indicate nonspecificity
04.05.2018 Static Semantic Properties 8
Semantic Properties of Entities
Specificity in Bemba
• aàfwaaya icitabo.
• a- à- fwaaya ici- tabo.
he past want Spec book
He wanted the specific book.
• a- à fwaaya ci- tabo.
he past want Non-Spec book
He wanted some (any old) book.
04.05.2018 Static Semantic Properties 9
Semantic Properties of Entities
Animacy
• Difference between biological and linguistic animacy
• Principle criteria for biological animacy: life and locomotion
• Principle criterion for linguistic animacy: influence of an entity over an execution of an event
• If an entity is more powerful or influential or valued it's more likely to be coded as animate → Animacy Hierarchy
04.05.2018 Static Semantic Properties 10
Semantic Properties of Entities
Animacy
• Every language distinguishes between animates and inanimates
• Cultural reasons for a certain classification
Yagua:
• Animate: persons, spirits, animals, stars, the moon, months, mirrors, pictures, rocks, pineapples, brooms and fans
04.05.2018 Static Semantic Properties 11
Semantic Properties of Entities
Animacy in Indonesian
• se- orang mahasiswa
one Human student
• se- ekor kuda
one Animal horse
• se- buah buku
one Inanimate book
04.05.2018 Static Semantic Properties 12
Semantic Properties of Entities
Sex and Gender
• biological sex is needed to be differentiated from grammtical gender
• sex is semantic property
• gender is a formal or coding property
• sex and gender do not necessarily match
04.05.2018 Static Semantic Properties 13
Semantic Properties of Entities
Sex and Gender
• in language only three sex distinctions are made:
• male, female, neuter
• Other not productive distinctions:
• e.g. entities with properties of both sexes
• e.g. castrated males
• different number of classes and different categorization in different languages
04.05.2018 Static Semantic Properties 14
Semantic Properties of Entities
Sex and Gender in Dyirbal
• Four noun classes
• Class 1: certain animals, culturally valued objects and all human males
• Class 2: water, fire, fighting implements, certain animals and human females
• Class 3: nonflesh food
• Class 4: the rest
• nyalŋga → child, bayi → Class 1, balan → Class 2
• Bayi nyalŋga → boy, balan nyalŋga → girl
04.05.2018 Static Semantic Properties 15
Semantic Properties of Entities
Kinship
• Familial relations among humans
• Relational System
• Focal point from which the rest of the system is seen = ego
• The other part of the relation = alter
• Three semantic properties: • Consanguinity: consanguineal vs affinal• Lineality: lineal vs collateral• Generation
04.05.2018 Static Semantic Properties 16
Semantic Properties of Entities
Kinship in Seneca
• ha?nih defines a paternal, male, consanguineal and one relation
→ Father
→ uncle on the father‘s side
→ great grandfather‘s brother‘s son‘s son
04.05.2018 Static Semantic Properties 17
Semantic Properties of Entities
Kinship in Mari‘ngar
• Quite different kin terms than in English• Tyan‘ angga → father‘s father / mother‘s mother
• Tamie → father‘s mother / mother‘s father
• Nea → man‘s child
• Mulugu → woman‘s daughter
• Magu → woman‘s son
• Wam:a → any third generation relative
• 18 basic kin terms at all
04.05.2018 Static Semantic Properties 18
Semantic Properties of Entities
Social Status
• Encoding of nonfamilial, social relations
• Every language has a way to signal relative social rank
• Four features of social status: stable, narrowly structured, gradient, encoded in a variety of forms
• Honorific: grammatical or morphosyntactical encoding of social status
04.05.2018 Static Semantic Properties 19
Semantic Properties of Entities
Social Status
• Social status = relation between two entities
• Relation between the speaker and
• The hearer → S/H System
• An entity spoken about → S/R System
• A situation → S/S System
• A bystander → S/B System
04.05.2018 Static Semantic Properties 20
Semantic Properties of Entities
Social Status in Japanese
In the S/H System:
• Ame ga hur- masi- ta
rain Subj fall Hearer Status fall
Speaking from me to you, and you have higher status, it rained.
It rained.
04.05.2018 Static Semantic Properties 21
Semantic Properties of Entities
Social Status in Japanese
In the S/R System:
• Yamada- sensei ga tegami o o- aki- ni nar- u.
Yamada teacher Subj letter Obj Hon write Subj High Pres
Respected teacher Yamada writes letters.
Teacher Yamada writes letters
04.05.2018 Static Semantic Properties 22
Semantic Properties of Entities
Physical Properties
• Focus on inanimate entities
• Physical properties: characteristics as spatial object
• Four general properties: extendedness, interioricity, size, consistency
• A number of others like arrangement, aggregates, time, material
04.05.2018 Static Semantic Properties 23
Semantic Properties of Entities
Physical Properties: Extendedness
• Two subcategories: dimensionality and shape
• Many languages encode dimensionality directly, some also shape
• Cree:
• Kinw- ēk- an
long two dimensions it is
It is long (i.e. like a piece of cloth)
04.05.2018 Static Semantic Properties 24
Semantic Properties of Entities
Physical Properties: Direction
• Distinction between vertically and horizontally extended entities
• e.g. in American Sign Language
• Toba: • nkotragañi ra- wakalče
he spills Vert Ext milkHe is spilling milk downward
• nkotragañi ĵi- wakalčehe spills Horiz Ext milkHe is spilling milk across
04.05.2018 Static Semantic Properties 25
Semantic Properties of Entities
Two Examples
• Yagua:
• Celina- jųy suuta- jááy- rà sújay mїї- jày.
Celina dual wash Near Past Inanimate cloth dirty Inan/2D
Celina (a married woman) washed the dirty cloth yesterday.
• Jacaltec:
• xul naj Pel b‘oj ya? Malin.
came Adult/Male/Non-kin Peter with Respect/Human Mary
An unrelated adult male, Peter, came with a respected human, Mary.
Peter came with Mary.
04.05.2018 Static Semantic Properties 26
Semantic Properties of Entities
Function
• In many languages there are ways of marking the specific uses of entities or the kinds of actions that are performed on them
• Wide range of functions encoded in different languages
• Often function-based classes are language-specific and connected to culture
• Only few regularities
04.05.2018 Static Semantic Properties 27
Semantic Properties of Entities
Function
• Common function properties:• Edibility
• Vehicular transport
• Speaking
• Cutting/piercing and the instruments for these actions
• Tzeltal: differentiates edibles by consistency, size, sweetness
• Yidiny: distinguishes between flesh and nonflesh food
04.05.2018 Static Semantic Properties 28
Semantic Properties of Entities
Boundedness
• Semantically bounded: inherently demarcated, already specified limits
• Semantically unbounded: inherently open, incircumscribed regions in conceptual space
04.05.2018 Static Semantic Properties 29
Semantic Properties of Entities
Boundedness: Features
• Features of the bound itself:• Boundedness
• depends on the universe of the discourse at the time of speech
• can be real or virtual
• is an inherent property of entities
• is fuzzy
• Features of internal structure:• Internal homogeneity
• Expansibility
• Replicability
04.05.2018 Static Semantic Properties 30
Semantic Properties of Entities
The Count / Mass Distinction
• Bounded entities are countable -> count nouns
• Unbounded entities are not countable -> mass nouns
04.05.2018 Static Semantic Properties 31
Count nouns Mass nouns
• can be pluralized• occur with indefinite
determiner• quantifiers as each,
every
• numeral modifiers
• always occur in singular• with measure terms
(much)• nondistributive
quantifiers as most, all and some
Semantic Properties of Entities
Issues of Mass and Count
• Standard presumptions:
• The locus of the distinction is the lexical noun
• The distinction is exhaustive and exclusive
• Account of the study: deny all these presumptions
04.05.2018 Static Semantic Properties 32
Issues of Mass and Count: Dealing with ‚Dual-Life‘ Nouns
Home of the Mass/Count Distinction
• Usual assumption: lexical noun is the home
• Problem:
• Mary put a little chicken into the salad
• Ambiguity
• Change from +COUNT to +MASS
→ Assumption doesn‘t hold
04.05.2018 Static Semantic Properties 33
Issues of Mass and Count: Dealing with ‚Dual-Life‘ Nouns
Goals of the Study
1. Investigate the possibility that the home of +MASS and +COUNT is not the lexical noun but a given sense of a noun
2. Display individual noun-senses that are simoultaneously +MASS and +COUNT
→ „Dual-Life“ noun-senses
04.05.2018 Static Semantic Properties 34
Issues of Mass and Count: Dealing with ‚Dual-Life‘ Nouns
Data
• Intersection of the nouns of the American National Corpus withWordNet
→ nouns with definitions
04.05.2018 Static Semantic Properties 35
Issues of Mass and Count: Dealing with ‚Dual-Life‘ Nouns
Annotation Task
• Six tests chosen for relevance to the study of the Mass/Count distinction
04.05.2018 Static Semantic Properties 36
Issues of Mass and Count: Dealing with ‚Dual-Life‘ Nouns
Test Outcomes
04.05.2018 Static Semantic Properties 37
• Senses grouped by the pattern of their answers
Issues of Mass and Count: Dealing with ‚Dual-Life‘ Nouns
Test Outcomes
04.05.2018 Static Semantic Properties 38
• Pattern for „dual-life noun-senses“: <yes, ¬num, yes, ¬equiv, yes, yes>
• 162 noun senses with this pattern
Issues of Mass and Count: Dealing with ‚Dual-Life‘ Nouns
„Dual Life“ senses
• Senses of Nominally-Oriented nouns (57):
• Nouns on there own
• Nouns compounded from nouns and possibly other non-verb partsof speech
• Senses of Verbally-Oriented nouns (96)
• Nouns that rely on a sense of a verb
04.05.2018 Static Semantic Properties 39
Issues of Mass and Count: Dealing with ‚Dual-Life‘ Nouns
Nominally-Oriented Nouns Senses
• Noun type associated with food
• Animal-designating meaning is count, flesh-designating meaning ismass
• „Fence-nouns“
• „-sides“ dual life group
• „-land“ dual life group
• Kind-Instance
• General meaning is mass and the more individual meaning is count
04.05.2018 Static Semantic Properties 40
Issues of Mass and Count: Dealing with ‚Dual-Life‘ Nouns
Verbally-Oriented Noun Senses
• Event-Result:
• Ambiguity of „event nouns“
• One meaning that describes the acitivty, action, event or process
• One meaning that describes the result of the activity
• e.g. collection
• e.g. emission
04.05.2018 Static Semantic Properties 41
Issues of Mass and Count: Dealing with ‚Dual-Life‘ Nouns
Verbally-Oriented Noun Senses
• Kind-Instance:
• Event-noun as a general term for a kind or type that has instances
• Event „meaning“ is seen as mass
• Instance „meaning“ is seen as count
• e.g. fantasy
04.05.2018 Static Semantic Properties 42
Issues of Mass and Count: Dealing with ‚Dual-Life‘ Nouns
Borderline Cases
• A few cases which seem to be equally Verbally- and Nominally-Oriented:
• regret
• Often difficult to distinguish between Verbally-Oriented Event-Resultand Kind-Instance relationship
• No sharp distinction
04.05.2018 Static Semantic Properties 43
Issues of Mass and Count: Dealing with ‚Dual-Life‘ Nouns
Event-Result vs Kind-Instance
• Event’s happening suggests a cause for the result → Event-Result "meaning"
• Event seems not to play any role in the formation, causation or extistence → Kind-Instance "meaning“
• Sometimes there are two possible perspectives on the relation
• e.g. imperfection#1: the state or an instance of being imperfect
• Such nouns manifest both types equally
04.05.2018 Static Semantic Properties 44
Issues of Mass and Count: Dealing with ‚Dual-Life‘ Nouns
Conclusion
• Home of the +MASS and +COUNT is a noun sense
• Dual-Life noun senses → distinction is not exclusive
04.05.2018 Static Semantic Properties 45
Issues of Mass and Count: Dealing with ‚Dual-Life‘ Nouns
One-shot Word Learning from Text only
• We found a cute, hairy wampimuk sleeping under a tree.
• Distributional models:
• Need hundreds of instances of word to derive a goodrepresentation of it
• Humans:
• Can infer a passable approximate meaning from only one sentence
→ fast mapping
04.05.2018 Static Semantic Properties 46
Distributional Modeling on a Diet: One-shot Word Learning from Text Only
Goals of the Study
• Can distributional models do one-shot learning of definitionalproperties from textual context only?
• Explore a plausible probabilistic distributional model for fast mappinglearning
• What kinds of overarching structure in distributional context and in properties are helpful?
04.05.2018 Static Semantic Properties 47
Distributional Modeling on a Diet: One-shot Word Learning from Text Only
Hypotheses
It is helpful to learn:
1. About similarities between context items
• e.g. eat-dobj and cook-dobj should prefer similar contexts
2. Co-occurrence patterns between properties
• e.g. from learning that an entity is mammal it‘s possible to inferthat it is four-legged
04.05.2018 Static Semantic Properties 48
Distributional Modeling on a Diet: One-shot Word Learning from Text Only
Data
• Quantified McRae dataset:
• Mc Rae dataset: set of 7257 concept-feature pairs
• Natural language quantifier expressing the proportion of categorymembers that have a property
• all -> 1, most -> 0.95, some -> 0.35, few -> 0.05 and none -> 0
• Animal dataset
• British National Corpus
04.05.2018 Static Semantic Properties 49
Distributional Modeling on a Diet: One-shot Word Learning from Text Only
Data
04.05.2018 Static Semantic Properties 50
Distributional Modeling on a Diet: One-shot Word Learning from Text Only
Models
• Count-based Models:
• Count Independent and Count Multinomial
• Implement neither of the two hypotheses
• Bimodal Topic Model:
• Implements both hypotheses
• Bernoulli Mixtures:
• Count BernMix H1
• Count BernMix H2
• Bi-TM BernMix H2
04.05.2018 Static Semantic Properties 51
Distributional Modeling on a Diet: One-shot Word Learning from Text Only
Results
04.05.2018 Static Semantic Properties 52
Distributional Modeling on a Diet: One-shot Word Learning from Text Only
Results
04.05.2018 Static Semantic Properties 53
Distributional Modeling on a Diet: One-shot Word Learning from Text Only
Results
04.05.2018 Static Semantic Properties 54
• bi-TM is much better→ confirms hypotheses
• AP varies widely across sentences• Average over all is close to
baseline• Most informative instances yield
excellent information aboutunknown context
Distributional Modeling on a Diet: One-shot Word Learning from Text Only
Conclusion
• Learning word properties it‘s helpful to use
• Distributional context
• Co-occurences of properties
• Combination of both
• Some contexts are highly informative
• AvgCos achieves some success in predicting which contexts are mostuseful
04.05.2018 Static Semantic Properties 55
Distributional Modeling on a Diet: One-shot Word Learning from Text Only
Mapping distributional to model-theoreticspaces
• Complementary of distributional semantics and formal semantics
• Would be desirable to have an overarching semantics whichintegrates distributional and formal aspects
→ Formal Distributional Semantics
04.05.2018 Static Semantic Properties 56
Building a shared world: Mapping distributional to model-theoretic semantic spaces
Motivation
• People can make complex inferences about statements even if theydo not have access to their real-world reference
• The kouprey is a mammal
• Systems can model entailment between quantifiers but rely on explicit representation of the quantifiers
• All koupreys are mammals → This kouprey is a mammal
• * Koupreys are mammals → This kouprey is a mammal
04.05.2018 Static Semantic Properties 57
Building a shared world: Mapping distributional to model-theoretic semantic spaces
Motivation
• Ambiguity of the bare plural
• Kim writes books vs Kim likes books
• Formalisation of the systematic dependencies between lexical and set-theoretic levels
04.05.2018 Static Semantic Properties 58
Building a shared world: Mapping distributional to model-theoretic semantic spaces
Goals of the Study
• Approach to automatically map a distributional semantic space onto a set-theoretical model
• Generation of high-quality vector representations
• Generation of natural language quantifiers from such vectors
04.05.2018 Static Semantic Properties 59
Building a shared world: Mapping distributional to model-theoretic semantic spaces
Data
04.05.2018 Static Semantic Properties 60
• Quantified McRae dataset• Animal Data
Building a shared world: Mapping distributional to model-theoretic semantic spaces
Experimental Setup
• Function f: DS → MT
• Transforms a distributional semantic vector for a concept to itsmodel-theoretic equivalent
• Mapping learned as a linear relationship
• Estimation of the coefficients via partial least squares regression
04.05.2018 Static Semantic Properties 61
Building a shared world: Mapping distributional to model-theoretic semantic spaces
Results
04.05.2018 Static Semantic Properties 62
Building a shared world: Mapping distributional to model-theoretic semantic spaces
Results
04.05.2018 Static Semantic Properties 63
• Spearman ρ: Degree to which predicted values foreach dimension in a model-theoretic space correlatewith the gold annotations
Building a shared world: Mapping distributional to model-theoretic semantic spaces
Results
• Category-specific training data yields high performance when tested on the same category
• System reaches human-performance on a subset of the data
04.05.2018 Static Semantic Properties 64
Building a shared world: Mapping distributional to model-theoretic semantic spaces
Generating natural language quantifiers
• Attemption to map the set-theoretic vectors back to natural languagequantifiers
• Goal: a system that produces quantified statements
04.05.2018 Static Semantic Properties 65
Building a shared world: Mapping distributional to model-theoretic semantic spaces
Generating natural language quantifiers
04.05.2018 Static Semantic Properties 66
• Conservative: prefers few to some and most to all
• Accuracy of producing „true“ quantified sentences = 73%
Building a shared world: Mapping distributional to model-theoretic semantic spaces
Conclusion
• Given a reasonable amount of training data for a category we can proficiently generate model-theoretic representations for concept-feature pairs from a distributional space
• Reaching human performance on domain-specific test sets
• Generating of natural language quantifiers from vectorialrepresentations
04.05.2018 Static Semantic Properties 67
Building a shared world: Mapping distributional to model-theoretic semantic spaces
References
• Linguistic Semantics by William Frawley
• e.g. Kiss et al. (*SEM 2017). Issues of Mass and Count: Dealing with "Dual-Life" Nouns
• Wang, Roller, and Erk (IJCNLP 2017). Distributional modeling on a diet: one-shot learning from text only
• Herbelot and Vecchi (EMNLP 2015). Mapping distributional tomodel-theoretic semantic spaces.
04.05.2018 Static Semantic Properties 68
Thank you for your attention
04.05.2018 Static Semantic Properties 69