Grammatical Formalisms
Postgraduate course «Technoglossia»
Stella Markantonatou
Athens, October 2012
LECTURE 3
Attribute-value pairs and of Feature Structures (FS)
CONTENTS
1.
2.
Attribute-Value constraints on CF Phrase Structure Rules ...................................... 1
Feature Structures (FS) ............................................................................................. 3
3.1.
Values in FS................................................................................................................ 3
3.2.
Reetrancy .................................................................................................................. 4
3.
References ................................................................................................................. 5
1. Attribute-Value constraints on CF Phrase Structure Rules
In Lecture 2, we used the notation below to express agreement constraints as an add-on
to CF phrase structure rules.
τα παιδιά τρώνε
S NP VP
VP V
(1) NP

Det
N (determiner –noun agreement)
Number
X
Number
X
Number
X
Gender
Y
Gender
Y
Gender
Y
Case
Z
Case
Z
Case
Z
In fact,
 we made explicit the description of the relevant properties of the values of the terminal
symbols, one by one. In the example above, the values of the terminal symbols are Det: τα, Ν:
παιδιά, and the “relevant” properties of them are Number, Gender, Case.
 we adopted an attribute-value style: the attributes are Number, Gender, Case and the values
X,Y,Z respectively.
 we imposed a set of constraints on the values of the attributes: We have required that all
Number attributes share the same value and so on with attributes Gender and Case
 we found a way to accumulate and check information as it comes rather than asking to process
it in a specific order.
Exercise 1: In (1) the same set of attribute-value pairs has been assigned to the nonterminal symbol NP. Consider the rule S NP VP and explain whether (1) is enough to rule
out all sentences with wrong subject-verb agreement. What should be done?
“Values” deserve more attention as they seem to be the carriers of valuable information
that is encoded in the Lexicon and percolates up to the rules. Consider (1) again. The
Lexicon would make available to (1) the information given in (2).
(2) The lexical entries for (1)
τα
1
Grammatical Formalisms
Postgraduate course «Technoglossia»
Stella Markantonatou
Athens, October 2012
Cat
Det
Number
pl
Gender
neut
Case
nom
παιδιά
Cat
Noun
Number
pl
Gender
neut
Case
nom
The terminal symbols of a CF rule lile (1) look for the value of the attribute Cat. So, (1) picks
up τα as a value for Det and παιδιά as a value for Noun. The constraints are satisfied.
Now, consider the following Greek data.
(3) Αγαπώ τα παιδιά. (Verb-object)
(4) Ήρθε από τα παιδιά. (Verb-PP)
Are the lexical entries (2) of any use anymore? No, because the NP τα παιδιά is in the
accusative case in (3) and (4). What do we do now?
As many minimally different entries as necessary can be created, however, the lexicon
becomes too large.
Τα
Cat
Det
Number
pl
Gender
neut
Case
acc
παιδιά
Cat
Noun
Number
pl
Gender
neut
Case
acc
Underspecification does not multiply the entries but requires a more powerful mechanism
of handling information. Below, Underspecification is modeled as disjunction.
(5) Τα
Cat
Det
Number
pl
Gender
neut
Case
acc V nom
(6) παιδιά
Cat
Noun
Number
pl
Gender
neut
Case
acc V nom
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Grammatical Formalisms
Postgraduate course «Technoglossia»
Stella Markantonatou
Athens, October 2012
Exercise 2: Consider (5) and (6). How do we know now that the subject of τα παιδιά
αγαπούν τις τηγανίτες is in the Nominative case? And why do we care?
Homework: The Cat attribute in (2) provides food for thought. It matches with the terminal
symbols of (1). Actually, (1) presupposes two matching procedures: the Cat attribute
matches the terminal symbols and the attribute-value pairs in (2) match those in (1). Now,
consider (7) below. How is (7) different from (1)?
(7)
Cat
Number
Gender
Case
Cat
Number
Gender
Case
NP
X
Y
Z
Det
X
Y
Z
Cat
Number
Gender
Case
Noun
X
Y
Z
This way of thinking will take us quite far – as we shall see shortly. Meanwhile, you are asked
to develop similar pictures for structures like (8)
(8) Τα παιδιά τρώνε μακαρόνια.
2. Feature Structures (FS)
(9) is an object that consists of a set of attributes and their values. It is called a feature
structure.
(9)
Cat
Det
Number
pl
Gender
neut
Case
acc
A bit of terminology: attribute is a homonym of feature in this context.
3.1. Values in FS
Values may be constants (9). They can also be feature structures (10), sets (11), lists or even
boolean expressions (5), (6).
(10)
Cat
Det
Number
pl
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Grammatical Formalisms
Postgraduate course «Technoglossia»
Stella Markantonatou
Athens, October 2012
Agr
Gender
Case
neut
acc
In (10), a new attribute has been introduced called Agr(eement) that takes a feature
structure as its value. There is no limit to the depth of a feature structure that appears as
the value of an attribute value pair.
In (11), (7) is reconstructed. The attribute Const(ituents) takes a set of feature structures as
its value.
(11)
Cat
Agr
NP
Number
Gender
Case
Cat
Const
Agr
pl
neut
nom
Det
Number pl
Gender neut
Case
3.2.
Cat
Noun
Number pl
Agr Gender neut
,
nom
Case
nom
Reetrancy
Consider (11) above. The values of the feature Agr are the same across the FS. This is not
accidental. Now, in the linguistic jargon we call accidental identity “token identity”. So,
identity of Agr values in (11) is not a token identity. Rather, it is a well-formedness
constraint on the FS that requires that all Agr features share exactly the same value.
It models Det-Noun agreement and at the same time percolates the same information on
the NP. We call such identity constraints “type identities”. (11) is a profound example of
type identity. Type identities model a particular kind of grammatical information.
If type identities are so important, there should be some way of declaring them on the FS.
We use the so-called reentrancies to denote type identity in FS (12).
(12)
Cat
Agr
1
NP
Number
Gender
Case
pl
neut
nom
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Grammatical Formalisms
Postgraduate course «Technoglossia»
Stella Markantonatou
Athens, October 2012
Cat
Det
Cat
Noun
Agr
1
Agr
1
Const
,
Exercise 3: Model subject- verb agreement with FS in the spirit of (12). Use reentrancies as
necessary.
Exercise 4: Consider the semantics of the sentences below. What kind of identity we should
use for (i) and what for (ii).
(i)
Ο Άρης είδε τον εαυτό του στον καθρέφτη.
Aris saw himself in the mirror.
(ii)
Ο Άρης είδε τον Άρη στον καθρέφτη.
Aris saw Aris in the mirror.
Exercise 5: XLFG https://signes.bordeaux.inria.fr/xlfg5/index.php
Implement this grammar (Lecture 2).
S (NP) VP (NP)
*S  V NP NP
NP  (Det) N (PP)
*VP  V (NP) (ΝΡ) (PP) (PP)
PP  P NP
Now, parse the following strings:
Έδωσα χρήματα.
Έδωσα του Γιάννη χρήματα.
Explain the results. How could you make them better?
3. References
Mary Dalrymple. 2002. Syntax and Semantics 34: Lexical Functional Grammar. Academic
Press
Ivan A. Sag and Thomas Wasow. Syntactic Theory: A Formal Introduction. CSLI Publications,
Leland
Stanford
Junior
University
(σημειώσεις
(http://hpsg.stanford.edu/book/slides/index.html)
Stuart M. Shieber. 1986. An Introduction to Unification Based Approaches to Grammar.
Chicago: Chicago University Press
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