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How to wirte a Grammar

WELCOME to our presentation. How to wirte a Grammar. SEMANTICS. Chapter 5. Jessica Kortyla, Ann-Kristin Tibo, Eva-Maria Nunnemann. SEMANTICS Introduction. …our grammar so far:. How to wirte a Grammar. 1) Head-Specifier Rule 2) Head-Complement Rule

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How to wirte a Grammar

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  1. WELCOME to our presentation How to wirte a Grammar SEMANTICS Chapter 5 Jessica Kortyla, Ann-Kristin Tibo, Eva-Maria Nunnemann

  2. SEMANTICS Introduction …our grammar so far: How to wirte a Grammar 1) Head-Specifier Rule 2) Head-Complement Rule 3) Head-Modifier Rule 4) Coordination Rule BUT: How is MEANING represented in our grammar? AND: What is meaning in general?

  3. SEMANTICS Introduction How to wirte a Grammar Reference and co-reference Many syntactic phenomena linked to meaning: reflexive pronouns (co-reference) subject-verb agreement singular and plural nouns mass vs. count nouns

  4. SEMANTICS Introduction How to wirte a Grammar We will look at how meanings of phrases and sentences are built up from the meanings of their parts • compositionality principle BUT the individualism of objects and substances is NOT fully determined by the structure of the world  depends on certain languages: e.g. „trousers“ and „Hose“ Semantic regularities associated to syntax lead to fundamental generalizations about linguistic structure!

  5. SEMANTICS Structure of our presentation How to wirte a Grammar What comes next?? • Introduction – Semantics & Pragmatics • Linguistic Meaning • Compositionality • Semantic Features • Predications • How Semantics Fits In • The Semantic Principles • Modification • Coordination Revisited • Quantifiers • Summary & Questions Introduction Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions HAVE FUN

  6. SEMANTICS Semantics & Pragmatics How to wirte a Grammar What‘s meaning in general? SEMANTICS & PRAGMATICS meaning is bound with action  communicative purposes: questions, assertions, commands Introduction Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions kind of meaning depends on the syntactic form a sentence has An example: question:Is Sandy tall? assertion:Sandy is tall.

  7. SEMANTICS Semantics & Pragmatics How to wirte a Grammar Communication has 2 components: Introduction Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions 1) linguistic meaning 2) reasoning about communicative goals

  8. SEMANTICS Semantics & Pragmatics How to wirte a Grammar linguistic meaning normally: literal or conventional meaning e.g. Do you have a quarter? something beyond that: request: Please give me a quarter this is pragmatics Introduction Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  9. SEMANTICS Semantics & Pragmatics How to wirte a Grammar Pragmatics How linguistic meaning interacts with situational factors and the plans and goals of conversational participants to achieve communicative goals Semantics Whereas semantics is the contribution to communication of the language Introduction Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions Semantics plays an essential role in explaining the communicative function of language in context!

  10. SEMANTICS Compositionality How to wirte a Grammar • Semantic Issues: • Which proposition is conveyed by a given declarative sentence? • Which question is conveyed by a given interrogative sentence? • DON’T WORRY!! • We have first to clarify: • What are the smaller units propositions and questions are constructed from? • How is the meaning of a given sentence determined by the meanings of its parts and the way of combination? • Introduction • Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  11. SEMANTICS Compositionality false How to wirte a Grammar “Kim is running“ The proposition you assert is either true or false, depending on a number of things. • Introduction • Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions The race was yesterday!! NO, my name is RACHEL!! Specifying truth conditions  specifying restrictions which must be satisfied

  12. SEMANTICS Compositionality How to wirte a Grammar • Truth conditions: • We need to guarantee that this sentence gets a semantics that is a proposition (not a question or directive) • Its semantics must be specified in terms of the following conditions: • there is a situation s • s is a running situation • the runner is some individual i • i is named Kim • s is temporally located around the time of utterance • Introduction • Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions true

  13. SEMANTICS Compositionality How to wirte a Grammar • Our grammar will be incomplete, unless we introduce • linguistic meanings of words and • a set of constraints  to correctly specify the linguistic meanings of phrase structures in terms of the meanings of their parts (their subconstituents) • Introduction • Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  14. SEMANTICS Semantic Features How to wirte a Grammar Semantic objects of our grammar: Classification in terms of the four basic kinds of meaning  four semantic modes • Introduction • Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  15. SEMANTICS Semantic Features How to wirte a Grammar • A semantic category with three features • a semantic MODE • an INDEX corresponding to the situation or the individual referred to • a restriction (RESTR) specifying a list of conditions that must be satisfied General semantic structure: • Introduction • Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  16. SEMANTICS Semantic Features How to wirte a Grammar Propositions Questions • Introduction • Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions Grammatical analysis has to ensure that we end up with exactly the right constraints in the RESTR list References Directives

  17. SEMANTICS Semantic Features How to wirte a Grammar Some general usages: indicesi, j, k, etc. as the INDEX values for the semantics of nominal expressions. The INDEX values s, s1, s2, etc. are for indices that refer only to situations. BUT, what’s about … …words and phrases which cannot be used to express a proposition, to ask a question, to refer to an individual??? e.g. determiners, prepositions, PPs, and conjunctions  MODE [none] • Introduction • Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  18. SEMANTICS Predications How to wirte a Grammar • What kind of entities make up the value of the RESTR list? • specifying relations among entities • Introduction of a type of feature structure called predication (pred) • The pred feature structure specifies: • 1) what kind of relation is involved, and • 2)who or what is participating in the relation • Introduction • Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  19. SEMANTICS Predications How to wirte a Grammar INSTance • Introduction • Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions s is a situation wherein i loves j s is a situation wherein i is happy RELatioN s is a situation wherein k is a book s is a situation wherein i gives k to j

  20. SEMANTICS Predications How to wirte a Grammar • Introduction • Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions • The restriction (e.g. book, happy, etc.) includes a predication of only one (nonsituational) argument • the feature is called INST(ANCE) • All predications are in principle situated

  21. SEMANTICS Predications How to wirte a Grammar • constraints that guarantee that the RESTR values of a phrase’s daughters are part of that phrase’s RESTR values. • Restriction value includes all the necessary restrictions on the relevant event participants  Let’s consider for example the simple sentence • Chris saved Pat. • Introduction • Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  22. SEMANTICS Predications How to wirte a Grammar Chris saved Pat. • Introduction • Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions • The conditions on situation s come from the lexical entry for the verb save • the constraint that i – the saver – must be named Chriscomes from the proper noun Chris. •  the constraint that j – the saved (person) – must • be named Pat comes from the lexical entry for the • proper noun Pat.

  23. SEMANTICS Predications How to wirte a Grammar • Introduction • Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions • the conditions of the parts of the sentence have to be amalgamated into a single list of restrictions. the Principle of Compositionality (Introduced later on)

  24.  two new features for the feature structures: SYN(TACTICS) and SEM(ANTICS) SEMANTICS How Semantics Fits In How to wirte a Grammar • Introduction • Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  25. SEMANTICS How Semantics Fits In How to wirte a Grammar  VPs have an index as their INDEX value  NP, S, VP etc. now include semantic and syntactic information features: SYN and SEM e.g. VPi is an expression for an VP whose SEM value‘s INDEX is „i“ here: the MOD value of that VP is modified as index „s1“ which is the same as the ARG value related to „today“ in the semantic restriction • Introduction • Linguistic Meaning How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  26. SEMANTICS The Semantic Principles How to wirte a Grammar Semantic Compositionality Principle Semantic Inheritance Principle • Introduction • Linguistic Meaning • How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions Semantic Compositionality Principle „In a well-formed phrase structure, the mother‘s RESTR value is the sum of the RESTR values of the daughters.“  a list whose members are those values  taken in order  + (sum operator) Example:‹A›,‹B,C›, ‹D› is the list ‹A,B,C,D› ‹A› + ‹B› = ‹A,B›, but ‹B› +‹A›= ‹B,A› and ‹A,B›≠‹B,A›

  27. SEMANTICS The Semantic Principles How to wirte a Grammar Semantic Compositionality Principle Semantic Inheritance Principle • Introduction • Linguistic Meaning • How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions Semantic Inheritance Principle „In any headed phrase, the mother‘s MODE and INDEX values are identical to those of the head daughter.“  „head-driven“ character

  28. SEMANTICS The Semantic Principles How to wirte a Grammar • Introduction • Linguistic Meaning • How Semantics Fits In The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions The two principles embody a simple powerful theory of the relation between the structures of the grammar and the meanings they convey!

  29. SEMANTICS Modification How to wirte a Grammar • Head Modifier Rule • As presented in chapter 4 • The only kind of modifier it accounts for is PPs • AIM: to extend it to adjectives and adverbs • PROBLEM: • (a) Adverbs only modify verbs and not nouns • (b)Adjectives modify nouns and not verbs • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  30. SEMANTICS Modification An example A rat died yesterday. * A rat yesterday died. The person responsible confessed. * The person confessed responsible. How to wirte a Grammar SOLUTION:Introduction of a new feature called MOD • Allows modifiers to specify what kind of expressions they can modify • Value of MOD: (possibly empty) list of expressions • For all elements that can be modifiers: the list contains only one expression • For all others: the list is empty • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  31. SEMANTICS Modification How to wirte a Grammar Lexical property of adjectives: [MOD <NOM>] (or [MOD <NP>]) Lexical property of adverbs: [MOD <VP>] (or [MOD <S>]) MOD is a VAL feature like SPR and COMPS MOD is passed up from the Head daughter to the mother via the Valence Principle • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  32. SEMANTICS Modification How to wirte a Grammar VALENCE PRINCIPLE Unless the rule says otherwise, the mother‘s values for the VAL features (SPR, COMPS, MOD) are identical to those of the head daughter No rule contradicts the Valence Principle with respect to the value of MOD  the MOD value of the mother is always the same as the MOD value of the head daughter • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  33. SEMANTICS Modification How to wirte a Grammar MOD like the other VAL features must be shared between conjuncts in a coordinate structure if not: licenses ungrammatical strings *The cat slept soundly and furry. *The soundly and furry cat slept. As the modifiers now specify what they can modify, the Head- Modifier Rule can be reformulated • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  34. Reformulated Head Modifier Rule: Head modifier rule licenses a phrase structure tree whose mother is a NOM when the head daughter is an expression of the category NOM and the modifier daughter‘s MOD value is also of the category NOM SEMANTICS Modification How to wirte a Grammar • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  35. SEMANTICS Modification How to wirte a Grammar • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  36. Head Modifier Rule also licenses a VP Assumption: the adverbs are lexically specified as [MOD<VP>] Both phrases can combine to: „A Student unaware of the regulations read persuasion quickly.“ SEMANTICS Modification How to wirte a Grammar • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  37. Value of MOD contains semantic as well as syntactic information Example: how semantics of modifiers work Pat aches today. Lexical entry for today: SEMANTICS Modification How to wirte a Grammar • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  38. The two semantic Principles, the Head- Modifier Rule and the lexical entries interact: SEMANTICS Modification How to wirte a Grammar • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles Modification Coordination Revisited Quantifiers Summary & Questions

  39. Nothing specifies MODE or INDEX values of coordinate phrases yet Coordination Rule as written in Chapter 4: Now this form will be used: SEMANTICS Coordination Revisited How to wirte a Grammar • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles • Modification Coordination Revisited Quantifiers Summary & Questions

  40. Predications expressing the meaning of conjunctions like and and or allow any number of arguments Example: Chris [[walks]1, [eats broccoli]2, and [plays squash]3]. [[Chris walks]1, [Pat eats broccoli]2, and [Sandy plays squash]3]. Representation: SEMANTICS Coordination Revisited How to wirte a Grammar • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles • Modification Coordination Revisited Quantifiers Summary & Questions

  41. s1 , s2, s3:simplex situations s0 :complex situation, involves all three simplex ones ; is the INDEX of the whole phrase  if a modifier attaches to the coordinate phrase: takes the INDEX s0 as its complex argument Revision of lexical entries for conjunctions: SEMANTICS Coordination Revisited How to wirte a Grammar • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles • Modification Coordination Revisited Quantifiers Summary & Questions

  42. Revision of Coordination Rule Rule accomplishes goals: All conjuncts must have identical values for SPR, COMPS, and MOD Collecting RESTR values of all daughters into the RESTR list of the mother Identifying the indices of the conjuncts with the semantic AGRs of the conjunction Identifying the index of the conjunction with that of the coordinate structure SEMANTICS Coordination Revisited How to wirte a Grammar • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles • Modification Coordination Revisited Quantifiers Summary & Questions

  43. Coordinate phrase structure satisfying the rule: SEMANTICS Coordination Revisited How to wirte a Grammar • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles • Modification Coordination Revisited Quantifiers Summary & Questions

  44. SEMANTICS Quantifiers How to wirte a Grammar Topic here: quantifiers and their scope ambiguities Example: A dog saved every family.  There are two different readings: 1) There was some particular dog that saved every family. 2) Every family was saved by some dog or another. Written in predicate logic: a) (Existi: dog(i))[(Allj: family(j))[save(i,j)]] b) (Allj: family(j))[(Existi: dog(i))[save(i,j)]] • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles • Modification • Coordination Revisited Quantifiers Summary & Questions

  45. SEMANTICS Quantifiers How to wirte a Grammar a. (Existi: dog(i))[(Allj: family(j))[save(i,j)]] b. (Allj: family(j))[(Existi: dog(i))[save(i,j)]] Quantificational relation:Exist, All Variable: i; j (only examples) Formula is called a quantifier‘s Restriction:dog (i), family (j) SCOPE: written in square brackets, follows the quantifier • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles • Modification • Coordination Revisited Quantifiers Summary & Questions

  46. SEMANTICS Quantifiers How to wirte a Grammar (Existi: dog(i))[(Allj: family(j))[save(i,j)]] the scope of (All j: family (j)) is: [save (i,j)] the scope of (Exist i: dog (i)) is: [Allj: family (j))[save (i, j)] The ambiguity of the sentence is caused by the different scopes. • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles • Modification • Coordination Revisited Quantifiers Summary & Questions

  47. Our representation: quantifiers treated in terms of predications Quantifier predication has three new features: Bound Variable (BV), Quantifier- Restriction (QRESTR), Quantifier- Scope (QSCOPE) Values of QRESTR and QSCOPE can be identified in RESTR list. SEMANTICS Quantifiers How to wirte a Grammar • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles • Modification • Coordination Revisited Quantifiers Summary & Questions

  48. Representation of different QSCOPE values: a. (Existi: dog(i))[(Allj: family(j))[save(i,j)]] b. (Allj: family(j))[(Existi: dog(i))[save(i,j)]] (a) Wide scope for the existantial quantifier: (b) Universial quantifier outscopes the existantial one: SEMANTICS Quantifiers How to wirte a Grammar • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles • Modification • Coordination Revisited Quantifiers Summary & Questions

  49. SEMANTICS Quantifiers How to wirte a Grammar • Only the QSCOPE specification changed ( see the tags) • Order of quantifiers on RESTR list remains the same • Assumption: each variable (i, j) introduced by a quantificational NP (e.g. every family, a dog) must be bound. • If no constraint is provided for the QSCOPE values, then the quantifier scope remains underspecified. • Generalised quantifiers expressed in a way that allows underspecified or partially resolved quantifier scope • Thus: simplified semantic representations for quantifiers as placeholders for more complete analysis used • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles • Modification • Coordination Revisited Quantifiers Summary & Questions

  50. Example for the determiner “a”: Value of BV should be the same as the INDEX of the noun for which a is the specifier. This identity can‘t be expressed within the lexical entry of the determiner The determiner identifies own index with the value of BV The lexical entry for a noun identifies its INDEX value with that of its specifier SEMANTICS Quantifiers How to wirte a Grammar • Introduction • Linguistic Meaning • How Semantics Fits In • The Semantic Principles • Modification • Coordination Revisited Quantifiers Summary & Questions

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