Feature structures
Number cat SINGULAR vs cats PLURAL
Number grammatical category of number cat SINGULAR vs cats PLURAL
Gender and number ragazzo msg tifel msg ragazza fsg tifla fsg ragazzi mpl tfal pl ragazze fpl
Grammatical categories
Criteria notional/semantic formal/morphological distributional/syntactic
1) Semantic: a. Nouns are words that name persons, places or things boy, garden, car, air, idea b. Verbs are words that describe activities work, sleep
2) Morphological: a. verbs: eats, ate, eat, eating, eaten, *ins, *smalling, *tablen b. adjectives: e.g. smallest, *eatest, *inest
3) Syntactic a. adjective: i) (the/a) man ii) (the/a) man is iii) very b. noun: the
Dual membership cut, peel
Subclasses verb: in/transitive, mono-transitive/ ditransitive, full/auxiliary, modal/ non-modal noun: common/proper, concrete/abstract, mass/count
Parts of speech (traditional word classes) a. open: noun, verb, adjective, adverb b. closed: pronoun, preposition, conjunction, interjection, particle, article/determiner, modals
a. terminal: N, AUX, V, DET, M b. phrasal: S, NP, VP, Pred
a. major/lexical categories: N, V, A, P b. minor/functional categories: Det, Aux, Mod, Comp c. grammatical categories: gender, number, tense, mood etc.
grammatical categories: gender: feminine, masculine, neutral, animate, inanimate, nominal class,... number: singular, plural, collective, dual, trial, paucal,... tense: present, past, future mood: active, passive,... etc.
gender: feminine, masculine masculine [- fem], unmarked feminine [+ fem] marked MASC FEM kiteb vs. kitb -et [-fem] [+fem] tifel vs. tifl -a [-fem] [+fem]
N V noun + - verb - + adjective + + preposition - -
+N -N +V A V -V N P
Italian noun +F -F +PL ragazzi ragazze -PL ragazza ragazzo
Back to feature structures
grammatical category of number cat SINGULAR vs cats PLURAL
cat [number: singular] cats [number: plural]
Feature structures [number: singular] [number: plural]
number: singular attribute/ value feature
Feature structures features values
Feature structures in different models of grammar LFG (Lexical Functional Grammar): f-structures GPSG (Generealised Phrase Structure Grammar): feature bundles, feature matrices, categories, FUG (Functional Unifcation Grammar): functional structures DCG (Definite Clause Grammars): terms PATR-II: dags (directed acyclic graph)
A feature structure is a set of feature-value pairs
feature value featurevalue pairs number: singular gender: feminine number: third
A feature structure can be represented as a directed acyclic graph (DAG) with: nodes = variable values paths = variable names
Feature matrix tifl-a number: singular gender: feminine
DAG number singular gender feminine
Feature structures as functions Feature structures are partial functions from features to values singular number plural feminine gender masculine f(number) = singular
... E.g. the squaring function e.g. n 2, 2 2 = 4, 3 2 = 9 etc. f sq (2) = 4 f sq (3) = 9 f sq (4) = 16
Features/feature names, attributes: number, gender, category, etc. Feature values: singular, plural, feminine, etc.
Values may be: atoms, feature structures ALSO: sets, binary, numeric, strings, lists
Atomic value [number: singular] atomic value
Feature structure as value agreement: number: singular gender: feminine feature structure as value
Feature and values feature value agreement: number: singular gender: feminine feature value
How can we represent categories as feature structures?
+N -N +V A V -V N P
The major lexical category noun Feature (name): N Feature value: + or Feature (name): V Feature value: + or
The major lexical category noun N: + V:
Feature (name): major category or mjcat Feature value: feature structure
Feature structure as value mjcat: N: + V: Do the same with verbs, adjectives, and prepositions.
(Partial) feature structure for the verb kiteb write mjcat: N: V: + agreement: number: singular gender: masculine person: third
(Partial) feature structure for the verb kiteb write mjcat: N: V: + agreement: number: singular gender: masculine person: third tense: past
Do the same for: kitbet she wrote ktibtu you(pl) wrote tikteb she writes niktbu we write
Using binary values + and for gender and number mjcat: N: V: + agreement: plural: feminine: person: third
Do the same for: kitbet she wrote ktibtu you wrote tikteb she writes niktbu we write
Using short forms as feature names mjcat: N: V: + agr: pl: fm: prs: 3