[developers] Lexical rules changing predicate symbols
Ann Copestake
aac10 at cl.cam.ac.uk
Sun Oct 9 19:29:42 CEST 2016
For me, the representation decision would come down to fairly fine
details of the semantics.
- Nearly all events have to be seen as having structure, which one can
potentially represent as subevents, so it would be difficult to argue
that causatives inherently have two events while other verbs only have
one. It's a matter of what the language makes accessible. Arguably,
having two events for causatives allows one to capture effects like:
The general immediately marched the soldiers quickly up the hill.
where `immediately' could modify the causation event and `quickly' the
marching, but there are similar cases with non-causatives:
Kim immediately ran quickly to the door.
which presumably means that Kim began running immediately. The
Generative Lexicon literature has a number of examples along these
lines. I'm not aware of any conclusive argument that means there have
to be two explicit events for English causatives.
- `the water spilled' does not imply that the event has a causer - it's
neutral about this. `The water spilled deliberately' seems very odd -
somehow it suggests that the water has a mind of its own - so it's not
simply the case that there's a semantically available unexpressed
subject. (There may be other considerations here - I don't know the
literature.) I would say that there's a semantic space corresponding to
spill_inchoative and a subspace of that corresponding to
spill_causative. While it would be nice if the ARG1 played the same
role with respect to both uses, we know that we can't do that in
general, so it doesn't bother me that ARG1 would map to the thing
spilled in one case and the causer of the spilling in the other -
because there are different predicates, that's completely fine, formally.
- what the ERG does for `spill' right now seems to me to be wrong,
because the predicate doesn't change between intransitive and transitive
forms. So there are no coherent inferences one can make about the ARG1
of the predicate spill_v_1 (in contrast to open, where at least one can
say that the ARG1 of open_caus is the causer and the ARG1 of open_v_1 is
the thing that opens).
- I don't see any inherent semantic problem with using an additional
consistently named argument in the situation where the causer is
mentioned, and I think it could make sense to say that the addition of
that argument takes the meaning into the causative subspace, if the verb
doesn't always imply there's causation. There's nothing semantically
wrong with:
The water spilled. spill(e) and SPILLED(e,x) and water(x) (neutral
about causation)
Kim spilled the water. spill(e) and SPILLED(e,x) and water(x) and
CAUSER(e,Kim)
but of course these aren't MRS style arguments.
- If what you want to do is a sort of halfway house between the two,
with a mix of MRS style arguments and actual semantic roles, I don't see
an inherent semantic problem, but there's a fair amount of argumentation
needed to justify that and also to explain it ...
All best,
Ann
On 07/10/2016 20:44, Joshua Crowgey wrote:
> Hello folks,
>
> Where this is probably relevant for Lushootseed is that the language has
> a system of derivational morphology which converts intransitives to
> transitives (causatives and applicatives), and this is present in nearly
> every word which denotes a predicate with more than one role player. I
> think it's worthwhile to consider this from the perspective of
> translations of these predicates: the correlates of almost all of the
> 'basic' transitive verbs of English are going to be built in Lushootseed
> from some sort of underlying, monovalent root and one of these
> deriviational affixes. I think it has been traditional to represent
> morphological causatives by positing a new event variable which
> represents the causing situation. But, I saw that there was no such
> variable in the English predicate symbols that we use for the
> translation equivalents of these Lushootseed sentences. For example
> (Hess LR1 p.18):
>
> ʔuk̓ʷəɬəd ti qʷuʔ
> PRF-k̓ʷəɬ-CAUSE DET water
> [Someone] poured the water
>
> ʔuk̓ʷəɬdxʷ ti qʷuʔ
> PRF-k̓ʷəɬ-CAUSE.OOC DET water
> [Someone] spilled the water
>
> This example shows how an unaccusative root k̓ʷəɬ 'be poured out' can
> form the basis for a 'causative' transitive predicate. Compare the
> lexical predicates such as _poured_v_rel and _spilled_v_rel in our
> English grammar which are arg12-relations. It's not clear to me that
> Lushootseed should have to posit two-event transitives just because the
> morphology shows how transitives are built. Looking at this the other
> way, should "Kim closed the door" require an event for Kim's causation
> as well as one for the closing?
>
> Those are the reasons why I started using a criticized MRS
> representation cheat---what Emily has called 'half-hog RMRS'. I had my
> transitivizing morphology add a predication which was to be interpreted
> as adding an argument to an existing e-type variable. I did this by
> sharing an ARG0. For me, the above sentences from Hess would be:
>
> _k̓ʷəɬ_v_be.poured_rel
> ARG0 e1
> ARG1 x2
>
> _d_x_CAUSE_rel
> ARG0 e1
> ARG1 x3
>
> _qʷuʔ_v_water_rel
> ARG0 x2
>
> (looking at this, I realize it's probably important to say that the
> examples above can take a subject marker: this valence position is
> introduced by the transitivizer even though it's not filled (or it's
> filled by 3rd person singular) in these examples above.)
>
> On my strange MRS, I wanted the interpretation to be something like:
>
> k̓ʷəɬ_v_be.poured_rel(e1, x2) & CAUSE(e1,x3)
>
> There are some akwardnesses about this to be sure, but for me it
> captured both the fact that I could see the structure of the wordform
> (ie, I could build the transitive from the intransitive) and that I
> didn't want the meaning to add additional events.
>
> So, with respect to Ann's examples in this thread, I think the main
> thing that I can see is that it may be useful for me to capture these
> relationships that I'm interested in without abusing the ARG0 in the way
> that I have been. In my case, there would actually be morphology for
> the lexical rule, which, if anything, I would think just strengthens the
> case for capturing this in the grammar.
>
>
>
> On 09/21/2016 03:18 PM, Emily M. Bender wrote:
>> Thanks, Ann. As for Lushootseed, I think we'd need some more data. Joshua,
>> does this discussion inspire any questions/ideas?
>>
>> Emily
>>
>>
>> On Sat, Sep 17, 2016 at 3:49 AM, Ann Copestake <aac10 at cl.cam.ac.uk
>> <mailto:aac10 at cl.cam.ac.uk>> wrote:
>>
>> Yes, I would be happy with that, except that I would suggest making
>> use of meaningful sense labels, at least as a mnemonic. So the
>> pattern on the rule would be
>>
>> _P_v_dance (e,x) <- LR -> _P_n_dance (x)
>>
>> The one could apply the rule productively, by specifying the
>> appropriate verbs as having predicates of the form _v_dance, if one
>> wanted. (The alternative is to just use the rule as a description
>> and explicitly state what it applies to, but since one could control
>> the application via an inventory of sense labels if the predicate is
>> decomposed and the senses correspond to types, I think this is
>> effectively equivalent.)
>>
>> What I would ideally want to say about the _dance_ component of the
>> predicate is that one should take it as commiting to the lexeme
>> implying dance when making inferences about the real world. I'm
>> deliberately stating this informally because what this actually
>> means is up to the grammar writer, but I would take it as allowing
>> that inference to be made by a computational system (using a robust
>> notion of inference!). This certainly does not commit one to saying
>> that all lexemes denoting dances will have this sense.
>>
>> For a language like Lushootseed this might not be enough to capture
>> the way that nouns and verbs behave, but at least it is a start.
>>
>> For what it's worth, I think of _tango_v_dance as corresponding to a
>> semantic space which is close to _tango_n_dance on most dimensions,
>> but shifted corresponding to the verb/noun shift. (There's been a
>> little experimental exploration of this sort of thing in
>> distributional semantics - there could be much more - but I'm
>> talking about some sort of idealised space now. What Aurelie and I
>> have called `ideal distributions' would work here.) In this
>> idealized space, these are subspaces of the dance n and v spaces.
>> And, for that matter _tango_*_dance (where * generalises over n/v)
>> has _tango_n_dance and _tango_v_dance as subspaces, and so on.
>>
>> Going back to what I was saying before, if one thinks there's a
>> meaning postulate that expresses the relationship between the verbal
>> and nominal form - e.g., something of the form:
>>
>> forall x,e [ _tango_v_dance (e,x) <=> exists y [ _dance(y) &
>> PERFORM(e,x,y) ]]]
>>
>> or whatever, where I'm using PERFORM as a placeholder, then the
>> alternative would be to express that in the lexical rule and not
>> have a separate predicate for the nominal sense. But then one would
>> have to work out a story about what the precise nature of the
>> relationship PERFORM (or whatever) is, and whether this can be
>> expressed in terms of properly motivated semantic predicates like
>> Dowty's DO, CAUSE and so on. Saying that there are related semantic
>> spaces is actually compatible with this but much more general -
>> obviously it's very vague, unless one starts to additionally express
>> constraints on the relationship between the semantic spaces. But my
>> own feeling is that doing these semantic relationships by
>> hand/symbolically is a dead-end (because there's lots of different
>> ones, and they have nuances and exceptions and so on).
>> The alternative approach of using systematic naming conventions for
>> the predicates allows us to make the connection explicitly visible
>> to some distributional component, without commiting to the actual
>> lexical semantics.
>>
>> All best,
>>
>> Ann
>>
>>
>> On 17/09/2016 05:29, Emily M. Bender wrote:
>>> Thank you for this follow up, Ann. I think I understand your view
>>> of things. Just one piece
>>> I wanted to follow up on this evening:
>>>
>>>
>>> On the other hand, as you said, there are other processes
>>> where the pattern is regular but with some exceptions, and
>>> where the precise semantic effect is difficult to pin down.
>>> Much of English derivational morphology falls into this class
>>> - it is useful to represent the relationship with the stem
>>> somehow, without claiming that we're capturing everything
>>> there is to say. e.g., "unkind" definitely has some
>>> relationship with (a sense of) "kind", and it's useful to know
>>> about that, but there are some idiosyncratic aspects of its
>>> meaning. Similarly, I'd say it's useful to represent the
>>> relationship between nouns denoting dances and the
>>> corresponding verbs (tango etc), which is productive, but I'm
>>> quite content to do that via a predicate changing operation.
>>>
>>>
>>> As I currently understand things, the change in the predicate
>>> symbol from _tango_n_1
>>> to _tango_v_1 would correlate with:
>>>
>>> (1) Change of type of ARG0 from x to e
>>> (2) Addition of ARG1 (of type x)
>>>
>>> ... or in the other direction:
>>>
>>> (1) Change of type of ARG0 from e to x
>>> (2) Removal of ARG1
>>>
>>> In other words, I think the predicate changing operation would
>>> also have concomittant
>>> changes elsewhere in the EP. Also okay? (This has implications,
>>> btw, for the analysis
>>> of Lushootseed that Joshua is working on, where there are lots of
>>> stems that seem to
>>> be happy to serve as either nouns or verbs.)
>>>
>>> Emily
>>>
>>>
>>>
>>> --
>>> Emily M. Bender
>>> Professor, Department of Linguistics
>>> Check out CLMS on facebook! http://www.facebook.com/uwclma
>>
>>
>>
>> --
>> Emily M. Bender
>> Professor, Department of Linguistics
>> Check out CLMS on facebook! http://www.facebook.com/uwclma
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