Intro (Dan): Motivation grew out of two experiences, one ancient, one more recent. In the LOGON project were working across frameworks and it was essential to be clear with Helge Dyvik about what properties of MRSs we wanted to try to enforce or sustain across these two grammars. Long, somewhat tedious meetings looking at lots of tedious examples. Didn't seem like the most efficient way to scale up to lots of language pairs. More recently working with Martin Kay's student at Stanford working with SRG and ERG for Martin's human-involved translation system. Were trying to map between SRG and ERG MRSs. They're pretty close. But inevitably places where the two languages headed us in different directions.

Issue of variable properties. In the ERG and at least a few other grammars, there's a [name].vpm (aka variable property mapping) file that makes explicit assumptions about paths to certain variables and map to an external format without paths -- flat representation. But we haven't come to agreement about what the names of those attributes and values can be. Even if we agreed on the attribute names, the values will be different across languages. My preference would be to sit down with the existing grammar writers and maybe one or two semanticists. Then build up a superset of possible values and agree on names for everything --- document to point people two. E.g., for number, will find 1, 2, 3 and not 1st, 2nd, 3rd. Agree on a conventional set of names. Grammar writers will then build a vpm file to sustain that mapping.

Went down that road somewhat for the ERG and Helge's grammar. Woodley has recently pointed out inadequacies in the current ERG. Maybe have a SIG on a methodology for arriving at that communication format. Is that worth our time, hopeless, done already? Grammars seem to never agree on this.

Oe: In part because the languages may differ, but also because grammars haven't been synchronized.

Emily: Person, number maybe. Gender is hopeless (the right way of doing this is coreference resolution, with gender filled in on the target side). Tense maybe, aspect if you can do it would have a very big superset. But Glenn is finding that a variable property is an awkward way to do it in Thai, might want EPs instead. Also, some languages seem to want additional variable properties, so the inventory of attributes across languages isn't fixed either.

Dan: That bleak picture suggests that maybe we should have a mechanism for bleaching MRSs for properties that might be annoying.

Ann: The gender property might be useful in some languages. So maybe not all or nothing.

Emily: VPM allows for this bleaching, as well as putting in default values on the way in.

Oe: Shows RmrsVpm page. Even if we can't agree on the 'upper' SEM-I (i.e. cross-linguistically valid statements about semantic interfaces), should consider making use of this machinery to only expose what we'd like to be visible in the external interface, and maybe also simplifying names (and paths). Example of PNG.PN <> PERS NUM on the page. pernum analysis makes sense English-internally, but it was agreed at a Cambridge meeting some years back that pulling apart person and number is preferable in the external MRS universe.

Ann: You want that hierarchy in the grammar because of the compositional properties, but those compositional properties are irrelevant for the exchange format.

Dan: Not just composition, but also morphological.

Ann: That's actually a case where it's possibly a mess for the exchange properties. There are some cases for German where going to exchange properties mean we can't underspecify anymore.

Dan: So it's a little bit lossy.

Emily: UW is starting on some sort of standardization with in the Grammar Matrix customization system --- soon starter grammar will have starter semi.vpm files, intended initially for monolingual use.

Dan: In some sense trying to harmonize this goes against our general skepticism about an interlingua. Here we've been pretending that there's potentially eventually a right answer about the variable properties. Maybe that's not right. I also talked with Glenn about aspect in Thai. Might be pushed back into using EPs in rels --- packing it into a variable property English is an illusion cross-linguistically. The underspecification of aspect gets trickier if rels. We had at one point treated tense as two EPs for each tense: once between reference time and event time and one between reference time and speech time (Reichenbach). Switched to variable properties as a more compact way of representing tense constraints, but not necessarily the right thing to do.

Ann: Has anybody ever written down what things like "past" mean in the SEM-I? Maybe past is obvious, but... in terms of Reichbenbachian theory or other theory or even just descriptively. Worried that it looks like we're getting similarity across languages, but cross-linguistically present, perfect etc. used differently even between English and German.

Oe: In LOGON we agreed that (most) variable properties merely expose morphosyntactic information and not really semantics. Convenient that it was in the variables (and thus more out of the way). Differences came up even in Norwegian-English pair.

Ann: Need to document what they mean in a language. If you were going to do it in some temporal logic would need to map to a different representation anyway.

Lars: Use ERG as standard reference point/interlingua, document other grammars by describing differences.

Dan: One place where that becomes awkward in Spanish-English pair. Spanish distinguishes two kinds of past. Don't have a morphosyntactic difference in English there at all. Need to build up a somewhat richer library that we would expose e.g., in the matrix.

Lars: Didn't mean interlingua. Accumulate pairwise contrasts as a step toward a more interesting thing.

Petya: Connection to yesterday's discussion of phenomena. The term "aspect" in Bulgarian means something different from other languages.

Dan: I like the idea of a step-wise approach where grammar writers talk pairwise and negotiate an agreement and write those down in the vpm or somewhere as comments. Then someone might use that as the basis for something to add to the Matrix.

Dan: Do we need to have a SIG sometime before Friday to push on this idea further, or enough already?

Emily: Are there other things beyond VPM?

Dan: VPM is first, since everything else is theoretical until that's solved. But there are others, e.g., underspecification of quantifier rels (between indef and def in jpn>eng translation). There may be others, but not today's talk.

Ann: SIG about methodology, how to go forward.

Dan: What we could do in small groups or pairwise. I'll take silence as consent and propose a SIG.

Francis: There's the low-hanging fruit of just spelling common names the same way.

SofiaVpmHarmony (last edited 2012-07-04 07:11:42 by StephanOepen)

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