Distribution

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Distribution or precedence refers to the study of the order of the syntactic constituents of a language.

Contents

Natural Language

In the UNLarium framework, the distribution is informed in the grammar, if general, or in the dictionary, in case of exceptions or categories that do not follow a regular distributional pattern (such as English adverbs).

In English, for instance, articles are always premodifiers. Therefore, distribution of articles must not be informed in the dictionary, but stated through a rule in the grammar. The same applies to determiners (such as "this") and ordinary adjectives (such as "beautiful"), whose distribution may be assumed by default: adjectives and determiners normally precede their modified. In that sense, distribution is to be associated to dictionary entries in the following cases:

  • Exceptions to the general rule, such as in some free order adjectives:
    • "it is the only solution possible" or "it is the only possible solution"
  • Categories with irregular distribution, such as adverbs:
    • Usually I get up early.
    • I often get headaches.
    • She speaks English well.

Representing distribution in the dictionary

In the dictionary, distribution is informed by assigning the following features to the base form and its constituents (in case of compounds):

Examples

  • very = BEF
    • In English, the intensifier "very" is a premodifier: He is very rich (He is rich very)
  • well = AFT
    • In English, the adverb of manner "well" is a postmodifier: He speaks well (He well speaks)
  • yesterday = FRE
    • In English, the adverb of time "yesterday" may come either before or after the modified: Now I go or I go now.

Observations

Middle position is used only for words to be inserted inside others (i.e., between the prefix and the root, or the root and the suffix).
Adverbs coming between auxiliaries and verbs must be defined as premodifiers.


Representing distribution in the grammar

In the grammar, distribution is defined through S-rules in the following format:

<SYNTACTIC ROLE>(<DISTRIBUTION>);

Where:

  • <SYNTACTIC ROLE> is the syntactic role (VA, VC, VS, VH, etc) of the constituent in relation to the head; and
  • <DISTRIBUTION> is the position of the constituent in relation to the head. It may assume one of the distribution values indicated above ("FNT","BEF",">>",etc).

Examples

VS(<<);
the specifier must be generated to the left of the verb
VC(>>);
the complement must be generated to the right of the verb

Observations

Complex distribution
A single distribution rule may contain several distribution operations:
  • VS(<<)VC(>>); (the specifier will be generated to the left and the complement to the right of the head)
Conditional distribution
Conditional distribution may be stated by defining the left side of the s-rule and coindexing it to the right side:
  • VC(>>); (unconditional distribution: the complement will be always generated to the right of the verb);
  • VC(PPR):=VC(<<); (conditional distribution: the complement will be generated to the left of the verb if a personal pronoun (PPR);
Reordering
Reordering can be done in three different ways:
  • By Ph-rules, if the process involves neighbour constituents and affects only the surface structure of the phrase;
  • By attribute change (i.e., deleting and adding distribution features), such as in "VC(->>,<<);" (i.e.,delete the "after" attribute and add the "before" attribute), in case of neighbour constituents or neighbour projections
  • By movement, in case of more complex inversions and extraction of constituents
The symbol ^ is used for negation and to control infinite recursion
  • VC(^>>):=VC(>>); (assign the "after" attribute to the complement of the verb if it does not have it yet)

UNL

Word order is not informed in UNL.

Software