<div dir="ltr">Dear all,<div><br></div><div>Sorry to be late to the party. I don't think there's much to add, but just in case</div><div>it's helpful, here's a brief summary of the kinds of cases I know about from the</div><div>Matrix grammarium:</div><div><br></div><div>(1) English loves its pronouns. Many other languages used dropped arguments</div><div>where English would put in a pronoun --- this can be specific to certain positions</div><div>(e.g. subjects in Spanish) or independent of argument position (e.g. rampant</div><div>pro-drop in Japanese). Sometimes only certain persons/numbers are droppable</div><div>or there can be other constraints. The argument optionality library in the Matrix</div><div>was developed by Safiyyah Saleem, and is written up in these publications:</div><div><br></div><div>Saleem, Safiyyah. 2010. Argument Optionality: A New Library for the Grammar Matrix Customization System. Masters thesis, University of Washington.<br></div><div><div>Safiyyah Saleem and Emily M. Bender. 2010. Argument Optionality in the LinGO Grammar Matrix. Coling 2010: Posters. pp.1068-1076.<br></div></div><div><a href="http://moin.delph-in.net/MatrixDoc/ArgumentOptionality">http://moin.delph-in.net/MatrixDoc/ArgumentOptionality</a><br></div><div><br></div><div>(2) As Mike and others have noted, dropped arguments can participate in control</div><div>relations. The tabe-sugiru `overeat' example isn't great (because Jacy probably has the</div><div>wrong representation of sugiru), but it's easy to construct other examples, such</div><div>as tabe-tai `[subject] wants to eat', and I'm sure the Spanish translation of such a </div><div>sentence would have the same property. For non-subject arguments we could</div><div>get such a reentrancy in the case of causatives `tabe-saseru' `x causes y to eat'.</div><div><br></div><div>(2') Depending on the representation of honorifics (as pointed out by Mike), they</div><div>might also fit in under this heading.</div><div><br></div><div>(2'') While we're at, there are information structural constraints about dropped</div><div>arguments (you can't drop focus), so we might have reason to posit an info-str type</div><div>ICONS for them. (I think Sanghoun discusses this in his thesis).</div><div><br></div><div>(3) We also see variable properties of dropped arguments recorded in the morphology</div><div>in many languages --- Spanish subject agreement is a familiar example here, but</div><div>we also see it for non-subject arguments in Zulu, Wambaya, Basque and many others.</div><div>If we're worrying about coreference chains, I think we'd want to include these.</div><div><br></div><div>(3') Another kind of variable property to consider is markers of definiteness/discourse</div><div>status. These are typically associated with the NP directly (choice of article as in English,</div><div>inflection on the head noun as in Scandinavian languages, presence v. absence of</div><div>an accusative case marker in I think Turkish and Farsi), and so wouldn't be apparent</div><div>in the case of dropped arguments, but it may be possible to find cases where the mark </div><div>is on the verb or on another argument.</div><div><br></div><div>(4) Trying to extrapolate Fillmore's work on definite/indefinite null instantiation to</div><div>languages like Japanese, my guess is that if there is generally available (definite)</div><div>pro-drop, but that particular predicates might also licenses indefinite null instantiation,</div><div>at least for non-subject arguments. Such that `tabeta' in Japanese could mean either</div><div>`You know who ate you know what' or `You know who ate something, but I don't expect</div><div>you to know what.' I haven't been able to substantiate this, though.</div><div><br></div><div>Possibly relevant (and possibly just naive) is this paper:</div><div>Bender, Emily M. and David Goss-Grubbs. 2008. Semantic Representations of Syntactically Marked Discourse Status in Crosslinguistic Perspective. In Proceedings of STEP 2008. College Publications. <br></div><div><br></div><div>(5) In Wambaya on variation on dropped arguments is arguments realized solely</div><div>by modifiers. Many of the examples involve numerals as the modifiers, so that's </div><div>maybe less interesting, but here is a more interesting example (from Nordlinger, 1998):</div><div><br></div><div><div>(4-158) Wurrudbanyi ngiy-a maganja murlu-ngunya-ni.</div><div> pull 3.SG.NM.A-PST digging.stick.IV(ACC) eye-PROP.II-LOC</div><div> The one that could see got the yam stick.</div></div><div><br></div><div>The suffix glossed PROP is a proprietive suffix which takes a noun and derives</div><div>a modifier meaning `having (noun)'. So here 'having eyes' means 'can see'.</div><div>II is a gender marker agreeing with the unexpressed subject. -LOC</div><div>is the case marker (actually ergative) indicating that this is a modifier</div><div>of the agent argument of the verb (pull).</div><div><br></div><div>Regarding tests, some ideas, though I'm not sure these are what you're looking</div><div>for:<br></div><div><br></div><div> * Trying to question the dropped argument:</div><div><br></div><div>(ia) I already ate.</div><div>(ib) What? (meaning what did you eat)</div><div><br></div><div>(ii) I already dined.</div><div>(iib) #What? (meaning what did you dine on)</div><div><br></div><div>Maybe this distinguishes dropped arguments from things that must be there</div><div>in the real world but aren't ever licensed as arguments?</div><div><br></div><div> * Using the dropped argument to refer back to a salient element</div><div>in the discourse:</div><div><br></div><div>(iiia) What happened to the cake?</div><div>(iiib) #Kim ate.</div><div><br></div><div>Whereas I think this would work fine in Japanese. Maybe that's because that's</div><div>a pronoun-type dropped argument in Japanese?</div><div><br></div><div>... gotta go run and make some slides.</div><div><br></div><div>Emily</div><div><br></div><div><br></div><div><br></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Tue, Jan 12, 2016 at 11:38 AM, Ann Copestake <span dir="ltr"><<a href="mailto:aac10@cl.cam.ac.uk" target="_blank">aac10@cl.cam.ac.uk</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000">
Thanks!<br>
<br>
I assume that the unexpressed argument cases like English `eat' are
different from dropped arguments in Spanish (and I guess Japanese)
because these apply across the board rather than being lexically
specific. I also assume it's clearer to a naive speaker that
something is `missing'. But I assume that putting back
zero-pronouns just for the case where there's a coindexation is not
something that one would want to try and do in a grammar - it
doesn't seem likely it could be done compositionally and
monotonically, if it could be done at all. <br>
<br>
Anyway, I will leave it up to others to decide what they want to do,
but let's leave it that I am willing to try and add support directly
in DMRS if that's thought to be helpful.<br>
<br>
All best,<br>
<br>
Ann<div><div class="h5"><br>
<br>
<div>On 12/01/2016 01:43, Michael Wayne
Goodman wrote:<br>
</div>
<blockquote type="cite">
<div dir="ltr">
<div class="gmail_quote">
<div>I think we're all in agreement that the reduced clutter
of DMRS and EDS is a good thing. I brought up the ICONS and
coindexed-dropped-arguments issues as examples where the
dependency representations are currently unable to be
equivalent with existing MRS representations, but I think
we'd all agree that we shouldn't just do whatever it takes
to make them equivalent. More below...</div>
<div dir="ltr"><br>
</div>
<div dir="ltr">On Mon, Jan 11, 2016 at 1:22 PM Ann Copestake
<<a href="mailto:aac10@cl.cam.ac.uk" target="_blank">aac10@cl.cam.ac.uk</a>>
wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hi all,<br>
<br>
On 11/01/2016 16:41, Stephan Oepen wrote:<br>
> if we were to add code to synthesize nodes for
variables that are not<br>
> introduced as the distinguished (or characteristic)
variable of any EP<br>
> but occur at least twice in an MRS, it would seem
natural to me to<br>
> leave these nodes unlabeled (they will not have
characterization or<br>
> other surface links either). this would also indicate
that they have a<br>
> somewhat different status formally (at least in terms
of<br>
> correspondences to a full MRS).<br>
<br>
we can't really leave them unlabelled in DMRS because they
wouldn't show<br>
up very well ... From my perspective, the alternatives to
changing the<br>
DMRS code to allow them are 1. put zero pronouns back into
JACY (without<br>
quantifiers) 2. add zero pronouns in some sort of
post-processing step<br>
3. add them to DMRS. Mike mentioned ICONS - but it doesn't
help here<br>
because the nodes that would have to be equated don't
exist. Or, at<br>
least, since ICONS can do absolutely anything, one could
define a<br>
variant of ICONS which did encode it properly, but it's
really too much<br>
of a stretch.</blockquote>
<div><br>
</div>
<div>In MRS, the ICONS solution might look like:</div>
<div><br>
</div>
<div>RELS: < ... [ ... ARG1 i5 ...] [ ... ARG2 i6 ... ] ...
></div>
<div>ICONS: < ... i5 equal i6 ... ></div>
<div><br>
</div>
<div>where i5 and i6 are the dropped arguments that refer to
the same thing (i.e., instead of coindexing the variable on
both arguments). However, you're right that this would not
naturally extend to DMRS, because it would require the
relation to encode the rargname of both the source and
target nodes. E.g., if we consider an extension to DMRS with
<icons> as a sibling element to <node> and
<link> elements:</div>
<div><br>
</div>
<div>...</div>
<div><icons></div>
<div> <iarg1
nodeid="10001"><rargname>ARG1</rargname></iarg1></div>
<div> <iarg2
nodeid="10002"><rargname>ARG2</rargname></iarg2></div>
<div> <ireln>equal</ireln></div>
<div></icons></div>
<div>...</div>
<div><br>
</div>
<div>I know. Yuck. Also, such graph would no longer be simple
nodes and links, but instead nodes and links and icon-edges,
which, at best, is harder to explain to DELPH-IN muggles. It
also feels like we're just flailing about pretending to know
nothing about the things we are equating.</div>
<div><br>
</div>
<div>So I now agree that the simplest and most enticing
solution is some kind of zero-pronoun, whether it's defined
by the grammar (solutions (1) and (2)) or by the DMRS
formalism itself (solution (3)). In addition, as you've
mentioned, a zero-pronoun would helpfully contribute a
nodeid that could be used for anaphoric pronouns in
discourse, if that is something we'll need later.</div>
<div><br>
</div>
<div>I believe the zero pronouns were dropped from Jacy
precisely because of the clutter. Japanese drops a lot of
arguments, and each one could result in two more
uninteresting EPs (the zero pronoun and its quantifier). On
a related note, my work on computing MRS isomorphism found
that a major factor that caused inefficient computation was
having many EPs with the same predicates (e.g., lots of
udef_q_rels). Therefore, I don't think it's a great idea to
reintroduce zero-pronouns in Jacy, unless we could constrain
it somehow (e.g., only for coindexation, without
quantifiers, etc.). I don't have strong arguments for
choosing (2) or (3). With (2), it might be easier to insert
variable properties on the zero-pronoun (e.g. evidenced from
verb agreement, like the dropped subjects in Spanish or
something), while (3) can help keep the representation
consistent across grammars (since its defined by the
formalism and not the grammar). (Aside: Japanese doesn't
have verbal agreement in terms of PNG, but it does encode
honorifics, even for dropped arguments. It would nice to
keep this information for the zero pronouns somewhere.)</div>
<div><br>
</div>
<div>Lastly, granting a nodeid for unexpressed arguments can
help with other ICONS relations (i.e., of the information
structure kind, not the variable-equating kind we were
talking about before) where one of the participants is
unexpressed.</div>
<div><br>
</div>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
> i share your sentiment that the disappearing of
unexpressed arguments<br>
> in our dependency graphs in general reduces clutter and
is desirable.<br>
> co-indexation of such (unexpressed) variables
admittedly challenges<br>
> that position. if we end up special-coding for these
cases, it would<br>
> be good to have the motivating examples and analyses
readily available<br>
> (and publicly vetted). i believe emily may have been
the first to<br>
> argue for such co-indexation, probably from her work in
the<br>
> grammarium?<br>
<br>
<br>
<a href="http://moin.delph-in.net/SingaporeMrsWellformedness" rel="noreferrer" target="_blank">http://moin.delph-in.net/SingaporeMrsWellformedness</a><br>
<br>
the example Mike gave was tabe-sugiru = eat-exceed = overeat<br>
<br>
while it would be very good if someone could write this up
or point us<br>
to a proper write up, I don't think there's much room for
argument about<br>
needing it for Japanese, unless one uses zero pronouns<br>
<br>
<br>
><br>
> —i recall we have talked once or twice in the past
about adding an<br>
> explicit distinction of unexpressed variables. for the
ERG at least,<br>
> i believe dan (and others) often look at ‘u’ and ‘i’
(and maybe ‘p’)<br>
> as varible sorts that indicate unexpressed arguments.
but that is at<br>
> best a convention and prevents stronger typing of
argument slots as<br>
> would be desirable. for example, the ARG2 of _eat_v_1
presumably must<br>
> always be an ‘x’ when expressed, but dan abstains from
putting that<br>
> type into the lexical entry because the scoping
machinery would<br>
> complain at ‘x’-typed variable without a quantifier.<br>
><br>
> would it work (and be desirable) to introduce a
variable property, say<br>
> [ XP bool ], to distinguish expressed from unexpressed
roles? i<br>
> imagine it would not be hard to make all constructions
that bind roles<br>
> specialize XP to true; one could then use the VPM
machinery upon MRS<br>
> read-out to default remaining (unspecific) XP values to
false.<br>
> alternatively, i imagine one could obtain the same
effect by making<br>
> the hierarchy of variable types a little richer, i.e.
put something<br>
> above at least ‘x’ and ‘e’ to indicate unxpressed
variants, say ‘w’<br>
> and ‘d’ (the immediately preceding letters :-).<br>
><br>
> any thoughts on actually introducing such an explicit
marking of<br>
> unexpressed arguments?<br>
><br>
> all best, oe<br>
<br>
The problem with handling unexpressed arguments `properly'
is that there<br>
are multiple different classes of unexpressed arguments, as
I outlined.<br>
In some cases in the ERG, verbs with optional arguments have
unexpressed<br>
arguments in the semantics, while other cases don't. This
also<br>
interacts with the desire to save on predicate names that
has caused<br>
many predicates to appear with different arities (which, of
course,<br>
isn't OK if one translates directly to a conventional
logical<br>
representation and has to be interpreted as some sort of
notational<br>
convenience).<br>
<br>
e.g., the ERG demo gives:<br>
<br>
Kim understood understand_v_by (e, x, p)<br>
<br>
Kim understood the sentence / Sandy understand_v_by (e, x,
x')<br>
<br>
Kim understood that Sandy was scared understand_v_by (e, x,
h, i)<br>
<br>
Kim ran run_v_1 (e, x)<br>
<br>
Kim ran the race / the store run_v_1 (e, x, x')<br>
<br>
Kim hoped hope_v_1 (e, x)<br>
<br>
Kim dreamed dream_v_1 (e, x, p)<br>
<br>
I don't find this intuitive but we don't have a test set or
criteria for<br>
*MRS which would make it clear why one representation is to
be preferred<br>
over another, and I find it hard to imagine what such
criteria could<br>
be. That's why I talked about anaphora in the previous
message, since<br>
that could have been an example of a clear cut difference,
though it<br>
seems (to me) it probably isn't. Failing such criteria, I
don't want to<br>
argue that there's a problem with the ERG representations
but it also<br>
means that dropping them gives one less thing to worry about
when we're<br>
actually using the output.<br>
<br>
So - I don't think it'll be a big hassle to add them to the
DMRS code,<br>
but I don't propose to add them to the DMRS formal
description and I<br>
don't think it's worthwhile expending energy on trying to
clean this<br>
up. There are ways to allow argument slot typing without
messing up the<br>
scope machinery, if that's something that needs to be fixed.<br>
<br>
All best,<br>
<br>
Ann<br>
<br>
<br>
<br>
<br>
</blockquote>
</div>
</div>
</blockquote>
<br>
</div></div></div>
</blockquote></div><br><br clear="all"><div><br></div>-- <br><div class="gmail_signature"><div dir="ltr">Emily M. Bender<br>Professor, Department of Linguistics<br>Check out CLMS on facebook! <a href="http://www.facebook.com/uwclma" target="_blank">http://www.facebook.com/uwclma</a><br></div></div>
</div>