Subcategorization frames

Revision as of 15:53, 2 September 2013

Subcategorization frames are sets of rules used to generate syntactic structures out of the base form.

What are subcategorization frames ?

Subcategorization frames are sets of subcategorization rules that apply for a wide range of cases, i.e., that are regular.

When to use subcategorization frames

Subcategorization frames are used in case of valent words whose syntactic needs follow a general rule, i.e., whenever there can be stated a regular pattern for generating constituents linked to the base form, such as specifiers, complements and adjuncts.

For instance, many verbs in English take a NP as a specifier (subject) and another NP as complement (direct object). This syntactic behavior, described by the frame VS(NP)VC(NP);, can be assigned to many different verbs and, therefore, must be defined as a subcategorization frame.

When not to use subcategorization frames

Subcategorization frames are not used in case of avalent words or in case of irregular behaviour, which is described by subcategorization rules.

For instance, very few verbs, in English, admit more than two arguments, such as "to bet" in "I bet you ten pounds that they lose". This syntactic behavior, which can be described by the rule VS(NP)VC(PPR)VC(NP)VC(CH([that]));, as very specific, is likely to be defined as a subcategorization rule, to be created inside the dictionary, rather than as a subcategorization frame, created in the grammar.

Reference

The subcategorization frames are referred as follows:

• by its common name (such as "intransitive", "direct transitive"), in case of well-established reference;
• by the rule itself, in case of single-rule frames;
• by the most distinctive rule, if any; or
• by a "leading form", i.e., a typical example (a prototype) representative of the whole category, otherwise.

There are two predefined frames in the UNL^arium:

AVALENT

If the word has valency equal to 0, i.e., if it does not require any argument.

IRREGULAR

If the word requires an argument but does not follow any existing frame.

Syntax

Subcategorization frames are expressed by S-rules, a special formalism for representing the syntactic structure of phrases.

<HD SYNTACTIC ROLE>(<ARGUMENT>);

Where:
<HD SYNTACTIC ROLE> is a head-driven Syntactic role (VA, VC, VS, VH, etc) of the term required by the base form; and
<ARGUMENT> is the term required by the base form to saturate its syntactic structure, i.e., in order to form the simplest maximal projection (NP, VP, JP, AP, PP, DP).

Observations

1. There must be as many syntactic roles as [[Subcategorization#Necessary_and_optional_arguments|necessary arguments] inside a subcategorization frame
   • VS(NP); (intransitive verbs)
   • VS(NP)VC(NP); (direct transitive verbs)
   • VS(NP)VC(NP)VC(NP); (a verb with two direct objects)
   • VS(NP)VC(NP)VC(NP)VC(NP); (a verb with three direct objects)
2. The arguments must be represented by their corresponding maximal projection (NP,VP,etc.) or by a XH relation in case the argument is necessarily headed by a given word:
   • VS(NP)VC(NP); (verbs taking a NP as specifier and another NP as complement)
   • VS(NP)VC(PH([of])); (verbs taking a NP as specifier a PP introduced by [of] as a complement = PH([of]);)
3. The arguments may have as many features as necessary, provided that they are necessary and represented according to the Tagset.
   • VS(NP,NOM); (verbs taking a NP in the nominative case (NOM) as specifier)
   • VS(NP,NOM)VC(NP,ACC); (verbs taking a NP in the nominative case as specifier and another NP in accusative case as complement)
   • VS(NP,PPR,NOM); (verbs taking a NP that is a personal pronoun (PPR) in the nominative case (NOM))

   Features of arguments may be omitted if they are default

   If the NP is always NOM in VS there is no need for VS(NP,NOM); the frame must be simply VS(NP);

4. Maximal projections must explicitly indicate the value of the phrase when they are fixed.
   • NS(DP([the])); (the noun requires the DP "the", i.e., the whole DP is fixed and cannot be modified)

   compare with

   • NS(DH([the])); (the noun requires a DP headed by "the", i.e., the DP structure is variable, provided that it is headed by "the")
5. Strings must be represented between "quotes" while headwords must be represented between [brackets].
   • VC(PH([of])); (the word "of" is supposed to be included in the dictionary and, therefore, must be represented as an [entry]
   • VC("to the lions"); (the expression "to the lions" is not supposed to be included in the dictionary and, therefore, must be represented as a "string"

Syntactic ambiguities

One single word may have different valencies. The English verb "to read", for instance, can be part of several different structures:

• Impersonal: John loves reading (avalent, i.e., no frame)
• Intransitive: John is reading a lot (monovalent: VS(NP);)
• Direct transitive: John read a book (divalent: VS(NP)VC(NP);)
• Ditransitive: John is reading the book to Mary (trivalent: VS(NP)VC(NP)VC(PH([to]));

Likewise, the adjective "surprised" may select different prepositions:

• Everyone was surprised. (avalent, i.e., no frame)
• Everyone was surprised by the news. (monovalent: JC(PH([by]));)
• Everyone was surprised at the news. (monovalent: JC(PH([at]));)

If these ambiguities DO NOT CHANGE THE CORE MEANING of the word (i.e., in case of polysemy), as in the cases above, they must be described inside the same frame according to the following procedures:

1. Different number of arguments

   The frame must represent the most complete possible structure made of necessary arguments:

   • to read = VS(NP)VC(NP)VC(PH([to]));

2. Different type of arguments

   The frame must bring all possible structures through the use of {|}

   • surprised = JC(PH({[by]|[at]}));

3. Different number and type of arguments

   The frame must represent all possible most complete structures:

   • To distinguish^[1]
     • Direct transitive: They have distinguished the mast of ships on the horizon. (VS(NP)VC(NP);)
     • Indirect transitive: They have distinguished between right and wrong. (VS(NP)VC(PH([between]));)
     • Ditransitive: They have distinguished him from the other boys. (VS(NP)VC(NP)VC(PH([from]));

     Frame: VS(NP){VC(NP)|VC(PH([between])|VC(NP)VC(PH([from])}

   • Angry
     • Why are you so angry? (avalent, i.e., no frame)
     • Why are you so angry about it? (monovalent: JC(PH([about]));)
     • Why are you so angry with Peter? (monovalent: JC(PH([with]));)
     • Why are you so angry with me for not doing this? (divalent: JC(PH([with]))JC(PH([for]));)

     Frame: JC(PH([with]))JC(PH({|[about]|[for]}));)

If the ambiguities CHANGE THE CORE MEANING of the word (i.e., in case of truly homographs), as in the case below, the entry must be split into different frames:

• To be

• to exist: I think, therefore I am. (monovalent: VS(NP); )
• to take place: "The test was yesterday." (divalent: VS(NP)VC({AP|PP});)
• to go: "I was in Italy". (divalent: VS(NP)VC({AP|PP});)
• copula: "He was good." (divalent: VS(NP)VC({NP|JP|PP|AP});)
• auxiliary: "He is going to Paris." (avalent: no frame)

Examples

Notes

1. ↑ The verb "to distinguish" is said to have several different senses:
   1. To perceive as being different or distinct.
   2. To perceive distinctly; discern.
   3. To make noticeable or different; set apart.
   4. To cause (oneself) to be eminent or recognized.
   5. To perceive or indicate differences.
   Some of these senses (namely 1,2,5) are somewhat inter-related, as they are associated to the core idea of "perceiving" and should be considered inside the same frame. The senses 3 and 4 are considerably different from the others (although related one to the other) and, therefore, must be described in a different frame, as indicated below.