LinGO Grammar Matrix v 0.6, October 15, 2003 (dpf)
This is a minor tuning of version 0.5, including a refinement of the KEYS
attributes, more normalization of predicate names (especially for messages),
some bug fixes in the syntactic rule schemata, and a few additional lexical
types. Details on these changes will be available in the soon-to-be-released
Matrix Users' Guide.
For those who have already developed a grammar baaed on the Matrix, the
following changes will have to be made manually in your language-specific
files in order to make them consistent with this version:
1. Changes in feature geometry
a. SYNSEM.LOCAL.LKEYS ==>
SYNSEM.LKEYS
The feature LKEYS has been moved up from LOCAL to SYNSEM, to shorten
this frequently mentioned path. (NB: As a related change, the type
'local-basic' which formerly introduced LKEYS has been deleted.)
b. LKEYS.--KEYREL ==>
LKEYS.KEYREL
LKEYS.--ALTKEYREL ==>
LKEYS.ALTKEYREL
These two attributes are the only pointers to relations in the RELS
list for lexical types, and since they are not shortcuts, the leading
hyphens have been dropped. (NB: Since the attributes --COMPKEY and
--OCOMPKEY are just shortcuts, the leading hyphens for these two names
remain as a reminder).
c. CAT.HEAD.KEYS.MESSAGE ==>
CONT.MSG
Since the message value of a headed phrase is not always identified
with that of its head daughter, it was an error to make the attribute
MESSAGE a head feature. This attribute is now moved to CONT, and its
name shortened for convenience to MSG.
2. Strings and symbols: RULE-NAME
The type 'symbol', which along with 'string' was a subtype of 'atom', has
been dropped, since the distinction between symbols and strings is not
useful, and was a source of potential confusion. So any attributes whose
values were of type 'symbol' should be changed to be of type 'string',
and values assigned to these attributes should be converted accordingly.
In particular, in subtypes of 'rule', the value of the attribute RULE-NAME
should be changed to be enclosed in double quotes; e.g.
[ RULE-NAME 'subj-head ] ==>
[ RULE-NAME "subj-head" ]
3. KEYS attributes
The attributes KEY and ALTKEY can have as values subsorts of the type
'predsort' (the same kinds of values allowed for the attribute PREDSORT
in semantic relations). These attributes enable a word or phrase to be
semantically selected by a predicate, and as head features they propagate
up from the lexical head of the phrase. For example, a verb can select
for a prepositional phrase headed by a particular preposition, as long as
the preposition has lexically assigned a specific value (a subtype of
predsort) to its SYNSEM.LOCAL.CAT.HEAD.KEYS.KEY attribute, and the verb
similarly constrains the KEY value of its PP complement (accessed via the
SYNSEM.LKEYS.--COMPKEY or --OCOMPKEY of the verb). Note that the values
of KEY and ALTKEY are of the same type as the values of the PRED attribute
within semantic relations, but it is not always the case that the KEY
value of a sign is identified with the PRED value of one of the relations
in its RELS list. Typically, closed-class lexical entries may identify
KEY and PRED values, but open-class lexical entries won't, since their
KEY value will be some underspecified subtype of 'predsort' (e.g.
'noun_rel' or 'verb_rel')
4. Relations and messages
The revisions introduced in version 0.5 for improved MRSs have led to a
potential confusion in naming of relations and their PRED values, so we
introduce a simple naming convention where all subtypes of the type
'relation' bear the suffix "-relation" as part of their name, and all
values of the attribute PRED (subsorts of 'predsort') within relations
bear the suffix "_rel" as part of their name.
In keeping with the reduction to a small number of subtypes of 'relation',
the value of the attribute MSG is now always the relation subtype 'message'
with appropriate values in the PRED attribute of the 'message' relation,
drawing from subtypes of the type 'predsort'. For example, in the type
'imperative-clause', the following change has been made:
imperative-clause := clause &
[ SYNSEM.LOCAL.CAT.HEAD.KEYS.MESSAGE command ]. ==>
imperative-clause := clause &
[ SYNSEM.LOCAL.CONT.MSG.PRED command_m_rel ].
5. Rules
This version incorporates several corrections and improvements to the
definitions of lexical and syntactic rules proposed by colleagues working
on the Japanese and Norwegian grammars, as follows:
a. In the definition of 'lex-rule', the order of appending of the RELS
lists has been reversed, for convenience.
b. The type 'basic-head-subj-phrase' no longer inherits from the type
'head-compositional' - this was an error preventing coherent MRSs.
c. The type 'basic-extracted-comp-phrase' no longer identifies the LEX value
of mother and daughter - this too was an error making the rule unusable.
d. The type 'basic-head-mod-phrase-simple' no longer identifies the value
of HOOK on mother and nonhead daughter, since this is no longer uniform
for scopal and intersective modifiers. Instead this identification is
done in the type 'scopal-mod-phrase'; in contrast, the type
'isect-mod-phrase' now inherits from 'head-compositional', identifying
the HOOK values of mother and head daughter.
e. In a related change, the type 'extracted-adj-phrase' is now restricted
to extracting intersective modifiers, so that the value of HOOK can be
correctly constrained.
6. Lexeme types
In order to capture the usual configuration of semantic constraints for
open-class lexical entries, the types 'lex-item', 'norm-lex-item', and
'lexeme' have been added. Some closed-class lexical entries, like those
for determiners in English, do not conform to the constraints in
'norm-lex-item', but most lexical entries will. We further add the
constraint that the outputs of lexeme-to-lexeme rules will conform to the
constraints in 'norm-lex-item'. We look forward to feedback, as always.
------------------------------------------------------------------------------
Grammar matrix v 0.5, August 15, 2003 (dpf)
This is an upgrade of version 0.4 of the grammar matrix, with some
further normalization of relation names and MRS feature geometry to be
consistent with the Copestake et al. paper, "Introduction to MRS",
being readied for publication.
If you have already developed a grammar based on the matrix, you will
need to make at least one set of manual adjustments to your
language-specific grammar files, since the location of the KEYS
attribute has changed, and the constraints on its attributes have also
changed. The KEYS attributes had been used in matrix-derived grammars
for two distinct purposes, first to simplify the notation when defining
lexical types, and second to express constraints on semantic selection
within phrases. The first usage was a convenient shorthand notation
which is irrelevant to phrasal signs, while the second is crucial in
constraining phrases. These two notions are now distinct in the
matrix, with the attribute LKEYS now containing these 'shorthand'
attributes convenient for defining lexical types, and the attribute
KEYS now made a HEAD feature. The attributes in KEYS are also more
strictly constrained, with KEY and ALTKEY no longer taking whole
relations as values, but only semantic sorts (see the User Guide for
elaboration). Likewise, the MESSAGE attribute now simply takes a
'message' type (or the distinguished type 'no-msg') as its value,
rather than a difference list.
Obligatory changes to make to language-specific grammar files:
(1) Where your grammar used the KEY and ALTKEY attributes to constrain
the properties of a selected constituent (complement, specifier,
subject, or modifier), change these values of KEYS.KEY and
KEYS.ALTKEY to be subtypes of the type 'semsort'. See the User
Guide for elaboration.
(2) Change these paths for SYNSEM.LOCAL.KEYS.KEY and ...ALTKEY to be
SYNSEM.LOCAL.CAT.HEAD.KEYS.KEY and ...ALTKEY
(3) Where your grammar used the KEY and ALTKEY attributes to constrain
the value of a lexical type's own semantic relations, change these
paths for SYNSEM.LOCAL.KEYS.KEY and ...ALTKEY to be
SYNSEM.LOCAL.LKEYS.--KEYREL and ...--ALTKEYREL
(4) Change the value of KEYS.MESSAGE by removing the diff-list brackets.
(5) Change the paths SYNSEM.LOCAL.KEYS.MESSAGE to
SYNSEM.LOCAL.CAT.HEAD.KEYS.MESSAGE
(6) Change the values for --COMPKEY and --OCOMPKEY to be the semantic
sort of the relevant complement, rather than the type of a relation
(again, see the User Guide for elaboration of semantic sorts).
(7) Change the paths SYNSEM.LOCAL.KEYS.--COMPKEY and ...--OCOMPKEY to
SYNSEM.LOCAL.LKEYS.--COMPKEY and ...--OCOMPKEY
In addition, you may need to make further adjustments, depending on
whether you have made explicit reference to the affected features or
types, which have been changed as follows:
(a) Deleted feature
The feature E-INDEX was introduced into the matrix for v 0.4,based
on its use in the ERG at the time for treating the semantics of
predicative PPs and gerunds. However, improved analysis of English
has removed the current motivation for this attribute in HOOK, so
it has been deleted from the matrix in order to be consistent with
the emerging MRS documentation.
(b) Renaming of type 'mrs-thing', and changes to its subtypes
The name of the supertype of 'individual' and 'handle' has been
renamed from 'mrs-thing' to 'semarg' (for 'semantic argument').
Also, one of its subtypes 'non-expl' has been deleted, since it was
confusingly redundant with the type 'event-or-ref-index'.
Corresponding adjustments have been made to the type hierarchy under
'semarg', though the leaf types remain the same.
(c) Renaming of other relations
To support a more consistent naming convention for relations, any
relation or predicate whose name formerly ended in "-rel" now has a
name which is like the previous one except that the hyphen ("-") is
always replaced with an underscore ("_"). An explanation of the
naming conventions can be found in the Matrix User Guide.
------------------------------------------------------------------------------
Grammar matrix v 0.4, March 10, 2003
This is a minor upgrade of the first version of the grammar matrix
(v 0.3), designed to standardize the feature geometry and naming
conventions for MRS feature structures, and to enable stronger
principles of semantic composition, as presented in Copestake,
Lascarides, and Flickinger (2001).
If you have already developed a grammar based on the matrix, you will
need to make the following manual adjustments to your language-specific
grammar files:
(1) Renamed features
Summary: Naming conventions now made consistent with soon-to-be-published
standard reference on MRS.
Recommended procedure: Do a global replace for each of the following in
all of your *.tdl files:
LISZT --> RELS
H-CONS --> HCONS
TOP --> LTOP
HNDL --> LBL
SC-ARG --> HARG
OUTSCPD --> LARG
SOA --> MARG
RESTR --> RSTR
BV --> ARG0
EVENT --> ARG0
INST --> ARG0
LABEL --> WLINK
(2) Introduction of HOOK attribute
Summary: The externally visible attributes of an MRS are now grouped
within a single attribute called HOOK, which is consistently used in
constructions to identify the properties of the semantic head daughter
with those of the phrase. The features in HOOK include the familiar
LTOP (formerly TOP), INDEX, and E-INDEX, as well as a new feature XARG
which is unified with the semantic index of the controlled argument of
a phrase (to simplify the definition of e.g. equi and raising types)
Recommended procedure: In each of your *.tdl files, search for each
occurrence of the three features LTOP, INDEX, and E-INDEX, and insert
HOOK into the path preceding each feature. In some cases, you will see
that you can simplify the re-entrancies in your feature structures by
referring to HOOK instead of individually referring to each of the three
attributes separately. In addition, consider revising your lexical types
for equi and raising predicates to make use of the new XARG feature,
which should enable you to avoid reference to arguments of arguments.
(3) Naming of argument roles (ARG1, ARG2, ARG3, ARG4)
Summary: Each relation now assigns its first (least oblique) argument
to ARG1, its next argument to ARG2, and so on. The major change from
the first version of the matrix is to assign objects of transitive verbs
to ARG2 rather than ARG3, and similarly for objects of prepositions.
Recommended procedure: In each of your *.tdl files, search for ARG3, and
consider replacing it with ARG2. Check all other role name assignments
to ensure that role names are assigned consistently.
(4) Basic relation types
Summary: The inventory of basic relation types has been simplified.
Recommended procedure: Review the subtypes that your grammar defined for
the original basic relation types, and revise them to employ the new
relation types, consistent with the changes made in step (3) above. Note
that a basic relation type has been added for quantifiers: quant-rel.
(5) Deleted features (--TOPKEY)
Summary: Some semantics-related features proved to be unnecessary
Recommended procedure: None required, unless your grammar makes use of
the feature --TOPKEY, in which case you may choose to introduce this
feature as part of your language-specific inventory of features.
------------------------------------------------------------------------------
[Original notes for v 0.3]
This is an extremely preliminary first cut at the grammar
matrix. It has not been tested except by being loaded into
the LKB. It contains the following:
-- basic types which define the feature geometry
-- types for MRS semantics
-- underspecified supertypes of lexical rules
-- underspecified supertypes of phrase structure rules
Of these, the last were the most hastily thrown together.
They are basically taken from the syntax.tdl file of the LinGO
English grammar, and then simplified by removing constraints
that are either likely to be specific to English or are
related to the LinGO analysis of coordination.
These phrase structure rule types are of necessity underconstrained
and merely instantiating them will surely lead to a grammar
with gross overgeneration. Thus, it is expected that they
will be either augmented directly, or via subtypes that fill
in some of the missing constraints. One clear example of this
is the lack of constraints on the HEAD values in phrase structure
rules. Since it's not clear what the appropriate 'universal'
head type hierarchy will/could be, I've refrained from even
defining types like 'verbal'...
Similarly, certain parts of the type hierarchy might need to be
modified. In an ideal world, the matrix type hierarchy would only
need to be extended at the bottom for individual grammars. However,
it is not clear that this is possible or desirable even in principle,
and it is certainly not the case for this preliminary first version!
(Defaults may help here...)
The single biggest gap in the matrix is the utter lack of
lexical types. I hope that it can be useful even with this
huge lacuna. Since the matrix holds so closely to the LinGO
grammar, the lexical types of the LinGO grammar should be
used as models for creating lexical types. Note in particular
that the rules assume lexical threading of NON-LOCAL features.
Beware that some feature names (notably HNDL) and many type names
differ between the matrix and the LinGO grammar, even when they
are logically and mnemonically related.
Future versions of the matrix should include further documentation
as well as more types (especially lexical types). Revisions to
the types included in this version should also be anticipated,
since it seems extremely unlikely that this first guess as to
what's universally useful will turn out to be entirely correct.
Stephan Oepen has kindly cleaned up the collateral .lsp files
included in this distribution of the matrix. Take a look at
lkb/script for information on how various files (including .tdl
files) are included, and which aspects of the grammar should
be encoded in which .tdl files.
April 5, 2002 (erb)
Added improvements to supertypes for lexical rules. "Derivational"
lexical rules are now lexeme-to-lexeme, rather than word-to-word
(a hold-over from PAGE). Lexeme-to-lexeme rules can be spelling
changing, and apply _inside_ lexeme-to-word, or inflectional rules,
as expected.
June 18, 2002 (oe)
Fix generator support (by adding a suitable `mrsglobals.lsp'); more
cleaning up of `script' and related collateral files.