Question Answering as an Annotation Format, with Luke Zettlemoyer

Guest: Luke Zettlemoyer
Hosts: Pradeep Dasigi, Matt Gardner, Waleed Ammar

In this episode, we chat with Luke Zettlemoyer about Question Answering as a format for crowdsourcing annotations of various semantic phenomena in text. We start by talking about QA-SRL and QAMR, two datasets that use QA pairs to annotate predicate-argument relations at the sentence level. Luke describes how this annotation scheme makes it possible to obtain annotations from non-experts, and discusses the tradeoffs involved in choosing this scheme. Then we talk about the challenges involved in using QA-based annotations for more complex phenomena like coreference. Finally, we briefly discuss the value of crowd-labeled datasets given the recent developments in pretraining large language models. Luke is an associate professor at the University of Washington and a Research Scientist at Facebook AI Research.

Matt Gardner

Hello and welcome to the NLP highlights podcast where we talk about interesting work in natural language processing.

Waleed Ammar

This is Matt Gardner and Waleed Ammar, we are research scientists at the Allen Institute for artificial intelligence.

Matt Gardner

All right. Today I have two new people to introduce because we are adding a new co-host to the NLP highlights podcast. Waleed and I, for a few reasons, decided it would be good to have a third person helping us. So we’ve asked Pradeep Dasigi who is also a research scientist at AI2 to join us as a co-host. Pradeep, welcome.

Pradeep Dasigi

Thank you. Hello everyone. It’s great to be here.

Matt Gardner

Do you want to introduce yourself very briefly?

Pradeep Dasigi

Sure. I’m a research scientist AI-2. I’ve mostly been working on question/answering and semantic parsing kind of problems. I’ve been a regular listener of this podcast and I’m really happy and excited to be part of this now.

Matt Gardner

Great. We’re glad to have you. And today our guest is Luke Zettlemoyer. Luke is a professor at the university of Washington and the scientist at Facebook AI research in Seattle and I had the pleasure of working with him for about a year at AI-2 when he was here. Luke, it’s really great to have you on the program.

Luke Zettlemoyer

Thank you very much, I’m super excited to chat about some stuff.

Matt Gardner

Yeah. I guess today at the topic I wanted to talk about with you is something that I guess you influenced my thinking on very heavily and this is how we can use question answering it as an annotation format instead of traditional formalisms. So I guess when you think about question answering in natural language processing, this community, I guess for a long time it was mostly focused on open domain, factoid QA or semantic parsing, which you, Luke have a lot of experience in, but more recently it’s been used for other things including as I believe you introduced this; as an annotation format. Do you want to explain what you did here?

Luke Zettlemoyer

Yeah. So I think that the idea is a little bit more general even than just QA, but we’ll talk about it mostly in the QA context. And the idea is that often when you label a data set, you want to, you know, get a model to predict some linguistic structure like predicate arguments, structure, connecting the verb to their arguments and seeing what kind of relationships they are or co- reference resolution, where you find all the noun phrases and cluster them and kind of the standard way of doing annotation tasks. You need to think of a really complicated annotation spec and think about all the linguistic phenomenon and maybe design an ontology for the possible relationships between things. Then very carefully go and label and it requires a lot of expertise and a lot of training to do this right. And so what we were trying to think about is, you know, how could you get labeled data, but in a way that’s much easier to train people to do.

Luke Zettlemoyer

So the general theme is that you could say what I’m going to do is take this linguistic phenomena or this other thing that I want to try to label and I want to try to reduce it. Even if it’s noisy, I want to try to reduce it to some end task that people understand. Something that we already know how to do very easily that I can train you in just a few minutes to understand because it’s essentially this other thing you already know how to do. And so question answering is a great example of that. So if I ask you a question, you can just read the text and you can answer it. And the way that we were doing it, the annotators actually have to write the questions and the answers. So it’s a little more complicated. But the idea is that with very little explanation you can get an annotation that closely matches what you’re looking for in linguistics because people know how to do these other tasks.

Luke Zettlemoyer

So this specific instance of this that we did was the QA SRL was the first version of it. And there it was semantic roles. So you know who did what to whom. And so, you know, if you have some sentence like, you know, “Luke is hoping that the interview that he is giving today is going very well, you know, blah blah blah blah blah.” Then you know, you have certain agents and patient relationships between various phrases in that sentence. But rather than getting a whole ontology and thinking of all the possible relationships, you could just say who’s giving an interview, what is the interview on, when is the interview happening, these kinds of things. And the answers to those questions will directly correspond to different semantic relationships you might want to label.

Matt Gardner

Yeah. So I guess we can think of this as using natural language to annotate instead of the formalism, right? So when you do this, there are going to be tradeoffs. So you mentioned you don’t have to do all of the work of like coming up with the ontology and defining and carefully training people on what the, what, what the distinctions are that you might care about between I don’t know, Arg0 and Arg1, for instance in semantic role labeling. But it feels like you lose something there when you don’t have that and you use language instead. Can you talk about these tradeoffs?

Luke Zettlemoyer

Yeah, I think it’s a, it’s a really great point and there’s always going to be trade offs and this case the philosophy was try to go as much as possible kind of ontology free. So we don’t want to sort of specify exactly what the possible relationships are and events. And, but that then you do lose something, right? Because for many end tasks you do need to reason about certain relationships. But the feeling was that maybe that’s more of a end task specific thing. So if you’re building an information extraction system, you may have your own ontology that you care about. You know, in terms of maybe famous people and the relationships they have to each other or you know, whatever sort of product you’re trying to build or whatever you’re trying to do with it. And then maybe it makes sense to sort of wait a little later to impose the ontology and that is the core NLP tool so just give you the structure and say, look, there is some relationship, that relationships can be described with these words. Now it’s not unique, right? There could be multiple questions that all have the same answer, but at least here are some words that can describe that relationship and then we can give that to someone later on that can think about how to make use of that as appropriate for what they want to do with it.

Matt Gardner

Yeah. I guess if, let’s say I really want a distinction between the temporal arguments to SRL and maybe a causal argument, I don’t know, maybe maybe this distinction is really important to me. You’re saying with this QA SRL formulation that perhaps a way to do this is get a lot of data cheaply from people to get the basic structure and it’s going to be unnormalized in some sense. And that the relationships will be labeled with language, but my downstream system, I can train it to make the actual distinction that I want to given the structure that I’ve recovered much more easily than I could have if I had just tried to do this distinction from scratch. Is that fair?

Luke Zettlemoyer

I hope so. Yeah. I mean, I hope that’s true. I think it’s still largely untested at this point, but I think that’s a good summary and this work was kind of happening, you know, in a different era of NLP before we had, you know, pre-training and so forth, really having huge impact. And so I think some of the original motivations are even a little different than how we might look back at it now and think about how to use it. But you could imagine that there are structural cues that you really need to get right, for example, for certain extraction tasks. In that, you know, just contextual embeddings or something else will actually allow you to do similarity and kind of sidestep a lot of the ontological issues. But again, you know, we’re also punting, right?

Luke Zettlemoyer

So, you know, FrameNet is an example of a SRL, formalism where they do just a really great job of designing a really interesting ontology and you learn generalizations across different forms of verbs and so forth. You know, some of them express the agent as the subject and some of them is objects and you know, these kinds of things and you, and so, you know, conceptually, if you had that ontology and it was perfect, you should be able to generalize better. Like you should be able to make use of it and we’re missing that opportunity. So it’s interesting in general.

Matt Gardner

Yeah, I agree. I want to come back to this pre-training point and how this whole idea fits into the new world of ELMo and BERT, RoBERTa and all of this stuff. But before we get there, I think it’d be interesting to talk about where else this applies, where else you’ve done it, where else we could take this general idea. So we’ve talked about QA SRL where you try to use question answering as an annotation format for semantic role labeling. You also have done QAMR, you would tell us about that.

Luke Zettlemoyer

So within predicate argument structure of a sentence. So they way you think about predicate argument structure or the way I think about it is, you know, like a little graph backbone of all the words and their relationships to each other. And you know, most of the work on the predicate argument structures is in semantic roles. So it’s only the edges between the verbs and the arguments. Although of course there’s some notable great work on doing nouns and other things too. But the majority of it is focused on verbs. And so when we did the QA-SRL annotation, we limited the set of possible questions that could be asked to set up templates, which designed very specifically to think about verbal predicate argument structure.

Luke Zettlemoyer

Now where you would like to actually get sort of a more complete semantics for the whole graph. Think of something like an AMR or Hooker representation or something like that, but the QA-SRL has no history about how to do that. So the QAMR effort was a effort to sort of relax and say, look, we’re not going to presuppose exactly what set of questions can be asked. We’re just going to say, look, ask any sort of simple question you could that is asking about relationships in this sentence. And it was an effort to try and get the annotators to actually show us what kind of edges should appear in these semantic graphs through their very free choice of what questions to ask and what answers to give. Julian Michael was really driving this work and he did a really great job of, you know, getting this to be crowdsourceable, being able to gather these annotations at scale.

Luke Zettlemoyer

Again, this was actually done in a different modeling era. So one of the challenges there was just like how to model this really interesting complex data that you got out. There were issues of completeness it was hard to know if you’ve got all the questions. But generally the questions we got were very good and then figuring out how to model with some incompleteness and with models that weren’t quite as good back then. I was quite challenging. So I actually think it’s probably worth revisiting now. Our models are so much better and you know, you can sort of have a fresh look at all of this, but that’s kind of where that project was standing at the time.

Pradeep Dasigi

So, right. You talked about QA-SRL and QAMR a, I guess going back to the idea of how general this formalism is are there at a high level, any limits on what kinds of linguistic phenomena? This formalism of question/answering can focus on?

Luke Zettlemoyer

Yeah, that’s a great question. I don’t know the answer. I mean I think that going back to the original inspiration, I actually like to think of it as take a semantic phenomenon and then reduce it to any end tasks you think of. So anything that you could have people do beyond just question answering. So by analogy, actually some of the most successful large datasets kind of have this property already. So speech recognition, like if I play an audio signal for you, I don’t have to teach you how to write a sentence. You know how to do that task already, right? Machine translation similarly. I mean you could argue about exactly what qualities the translation should have, but people already know how to do that task. Actually, part of the motivation before pre-training was to get a lot of data.

Luke Zettlemoyer

If you want to ever get a lot of data for a task, you need to reduce it to something that people already know how to do. Okay. And so you could take an extreme stance here, which I don’t know if I believe, but you can take an extreme stance that anything that we should aim to recover in language should be reduceable to something that people already know how to do. That’s a little bit extreme, but I would love to kind of push that agenda and say like, you know what can’t you do this way? It’s not all going to be QA. I think QA is more things where you’re trying to identify a span of text. Cause often you, you know you have a question and the answer is a span and the question is kind of telling you the relationship between one or more spans of texts. So I would think most tasks hopefully that were relationships between spans of texts could be done, but I don’t know how to prove that. But more generally I hope that this idea would go far beyond that to kind of anything that’s reducible to some tasks that we already know how to do.

Matt Gardner

Yeah. I think the decompositional semantics initiative by Aaron White and Benjamin Van Durme and others, we interviewed Aaron White on the podcast a few episodes ago. I think that it’s very much related to this idea that they’re pushing on a few different areas of semantics that way.

Luke Zettlemoyer

Yeah, I love that story. And it’s, and one way to think about that is that it’s more about like at least the earlier versions, I’m sure that generalized it, but it was a really nice idea of like what should the labels be, you know, on the edges, right. Which we’re sort of almost punting in the QSRL, we’re more asking which spans of text should be connected by an edge and they’re thinking more about like what is the right set of labels and how do you decompose that space. And I think it’s very complimentary. Like I was pretty excited when I saw that work for the first time.

Matt Gardner

Right. Jumping back to QAMR a little bit, just to give a concrete example of this. So semantic role labeling is verbs largely and what nouns attach to the verbs, and as you said, QAMR tries to do more general structures. One example of this might be Facebook scientists, Luke Zettlemoyer as part of a larger sentence, but you would questions just about that noun phrase, right? What kinds of things might you see?

Luke Zettlemoyer

Right? So I think you would see things like, you know, what’s a Luke’s job or what kind of job does he have? So more what kind of questions? In general, you know noun, noun compounds often have very complex implicit relationships, right? So this is one example of that. But you can also say things like baby food, you know, it’s food that babies eat, right? It’s not no food made out of babies. That is what everybody’s classic example is. Whereas in other noun noun compounds that actually express, you know, what the thing was made out of. So, you actually see that kind of stuff showing up in the data. You say if you show somebody a noun noun compound or you say, you know, try to use this word in the question, this other word in the answer. They’ll think about what’s the relationship and they’ll express it in natural language and that was one of the cool things that popped out with that data and you see it also in all kinds of other situations, not just in noun noun compounds where you have implicit relationships that aren’t explicitly specified with the word. So that was pretty cool.

Matt Gardner

Yeah. I guess earlier we brought up trade offs between formalism based annotation and natural language based annotation and one nice thing that you get from QAMR is this flexibility that the annotator can inject, giving you information that’s not there and that would be super hard to capture in a formalism. How do you even write down a formalism that says like there’s this employment relationship? I guess you could try to characterize all possible noun compound relationships but…

Luke Zettlemoyer

There is some great work for sure on a bunch of really nice papers I’m doing noun noun compounds. I think Vered Shwartz has done some really great work in that area. I just happen to know her work. It’s not something I know that well in general. So there are some people that have thought about that. But I do think that there’s a potential to be more scalable when using natural language as the ontology because you don’t have to specify that. You can sort of explore it as you go and see what falls out.

Matt Gardner

Right. And and language is productive. People come up with new uses for these things like Watergate and how that turned into Pizzagate and all kinds of other gates and like there’s new stuff that’s just going to be hard to fit into an ontology no matter what you do. And so that, that’s really a really nice thing about using language itself as an annotation format.

Luke Zettlemoyer

Yeah. And again, you know, ontologys are useful. So you are giving something up but then you’re getting some flexibilities. I totally agree.

Pradeep Dasigi

Right. So that’s one advantage of using QA as a format, right. You get more information from the annotators. Are there any other advantages in terms of how you can use that data? Does say QSRL open up new avenues for using the data that you’re getting or building models using that data that a set of data for example, can you pretrain question answering a model on QARSL and use it for other downstream tasks? Other advantages like that?

Luke Zettlemoyer

Yeah, I mean, that’s a great question. We should investigate the pre-training avenues more. We haven’t done enough of that. That would be the sort of dream would be that you could scaffold BERT or something a lot like you can do with MNLI where you sort of first fine tune on QASRL then fine tune something else. We haven’t shown that. Like we haven’t just haven’t had a chance, you know, there’s only so much time in the day. I think it would be a fun direction to explore. I’m a little nervous that, you know, a lot of this stuff is in there already in terms of the predicate argument structure. But another interesting angle beyond just kind of core numbers on tasks is interpretability too. So you know, if you’d like to be able to express to users what relationships you think exist in a text and natural language is a pretty natural way to do that.

Luke Zettlemoyer

So if your models can predict in this space, maybe you know, maybe they can better explain why they’re sort of making predictions they’re making. And we did some very small version of this last year on the large scale QASRL parsing where we sort of showed that the model can predict what semantic edges. You want to, the model actually predicts the questions and then you show the question to users or crowdsource workers and have them answer. And then you know, you can sort of do this kind of active learning are human and Luke kind of parsing because everybody’s working in a space where we all understand the relationships and so I can show you my predictions. You can correct, conceivably you could even show me your predictions. I can learn from, you know, this whole interesting sort of interaction that can happen. I still haven’t given up on like moving the core numbers, but I also think there’s other ways of thinking about the usefulness.

Matt Gardner

So I know that you also had a project, a at least briefly trying to get this same question answering as annotation, idea working for co reference resolution. But I think you ran into a bunch of challenges there. Do you want to tell us about this?

Luke Zettlemoyer

Yeah, that’s a great question. I really like thinking about sort of how to push this in different directions. We sort of just did some preliminary piloting. We didn’t ever try to like launch a full project. I actually think it’s still pretty doable, although we could probably talk to the poor students that had to suffer through the pilots and see what they think. One interesting thing we found in the original QASRL and also in the QAMR is that people resolve co reference when they do QA, they just do, right? So if you say, you know, “Luke is excited that he’s having an interview”, then you know, say who’s having an interview, they’re not going to answer he, they’re going to answer Luke.

Luke Zettlemoyer

Right. So one of the small tweaks we had to do in the original data annotation was to train people to answer in pronouns, not antecedents. So it turns out that you know, this just happens naturally and I think that gives you some leverage for thinking about how to crowdsource co-ref. That’s not perfect. But if you can figure out which phrases are referential are referring back to something and then you know, think about the local relationships and design questions I would ask about those phrases. You’ll often get antecedents as answers if you don’t train them not to do it. I still think it’s a pretty exciting direction. Something that we would still like to work on in our preliminary studies kind of showed that it does work, but you have to be a little bit careful about exactly which questions you ask and think about how to do it scalably and so forth.

Luke Zettlemoyer

And there’s another caveat, which is that co-reference is a very complex phenomenon and the types of co-reference that are on ontonotes, I mean ontonotes has done a great job. That’s our reference data set in this area has done a great job, but you know, it’s done that by, by carving off a well circumscribed set of co-reference phenomenon and there’s all kinds of weak co-reference, bridging co-reference and other things that happen that would, you know, potentially just fall into the QA formulation. That’d be great. But it would be maybe harder to map it back to what we already know, which is, you know, pluses and minuses to that.

Matt Gardner

Yeah, definitely. I remember reading a paper a long time ago by a Marta Recasens and Ed Hovy and maybe others about near identity coreference relationships and how it’s really hard to define even like some of these relationships and again, thinking about trade-offs. This is another place where it really seems like it’d be useful to use natural language as an annotation format so you don’t have to box yourself in too much with the formalism that might not capture what’s actually going on in the language.

Luke Zettlemoyer

Yeah, I think it’s super exciting. I mean you could argue that as it field in general, we should be trying to push more of the boundaries of the task definitions. You know, in many ways the tasks we’re solving are just overly simplistic because we didn’t even know how to dream about doing harder tasks a few years ago and you can argue that now we’re ready for that. You know, a lot of tasks are quote “human level performance” and it’s time to start thinking about sort of newer, harder things, which won’t be too difficult, I don’t think, to find, although it’s always hard to get annotations. So you know I have a lot of respect for people to make data sets, but I just mean that phenomenon there’s lots of them.

Matt Gardner

Talking about this co-ref and new datasets, harder problems. I think it’s a good time to talk about some work that Pradeep did that I think is very related. You want to tell us briefly about co-ref and how this fits in.

Pradeep Dasigi

Right. We built this new reading combination data set called Quoref. That’s whit a Q, so it’s a question answering dataset that uses co-reference resolution. So the ideas as Matt mentioned, it’s quite similar to ideas that Luke was talking about in terms of a building question answering for co- reference resolution. Although what we did was not necessarily to get questions that talk about all possible co-reference resolutions in a given context but instead we wanted to build a hard reading comprehension dataset that condensed questions that require co-reference resolution. The dataset itself is a span selection question answering dataset very much tech SQuAD except that before you get to the answer for most of the questions you are required to resolve co-reference in the given context to get to the answers.

Matt Gardner

As you were talking about your co-reference project, I think it’s very similar to what we did here.

Luke Zettlemoyer

The hope would be to try to get a more dense annotation would be one of our goals, but I really like what you did there balancing sort of the co-ref that you actually need to do QA, and that seems very clever to me. This is going to be a really nice piece to bite off and I should say actually one of my PhD students is looking at the data and we are pretty impressed. It’s pretty high quality. So maybe we’ll do some modeling there. We have also done a lot of work on just like models for co-ref and models for QA. And I think a big challenge right now in the field is, you know, how do you get more reasoning into these big deep learning models.

Luke Zettlemoyer

And I hope that coref will be one of the cases where you can get something a little more explicit in some models or you know, if it’s not some sort of interesting discrete reasoning, at least show that the models are somehow doing that implicitly in all those mini perimeters in as many layers as they feed forward. Just trying to understand that relationship, how to do it. So that’s the reason why we sort of found your data pretty interesting. And something that I’ll look at. You know there’s a few datasets now that have done various trying to encourage more reasoning, but I think there could be a lot, lot more.

Matt Gardner

So this is something I’ve been thinking a whole lot about recently and I’m curious to know your thoughts Luke, I’ve been trying to figure out what it means to get a machine to actually read a paragraph and understand it. I don’t think we have any formalisms that touch on this really at all. We have like predicate arguments structure, but that’s like very local kinds of stuff. There’s discourse parsing, but that’s not really the same thing. Like what, what does it mean to understand and how do we define this? And it seems like the only thing I can come up with is this idea that you have of question answering as annotation for various kinds of of Symantec phenomenon.

Luke Zettlemoyer

I’m sure there’s a lot of semantics you can’t reduce to QA, just think about like sentiment types of things and sort of you know, complex sort of pragmatic implications and so forth. But it would certainly be a great first step and beyond predicate argument structure. You also have quantification and sets anednumbers. You guys have a great data set on reasoning with numbers and texts. I think actually Tom Dietterich kind of pretty cool posts pretty recently where he sort of talked about these issues of like, well you know, even if we can’t, you know, sorta just talk about levels of understanding, not understanding one discrete unit that resonated with me. It’s not something I had thought about before that, but you know, I think we should, the goal shouldn’t be necessarily defined what understanding is, but sort of what the next level is and how can we jump five levels or how could we jump 10 levels, whatever that means.

Luke Zettlemoyer

And I think one really nice way of doing that is, is designing ever more complex questions that seem to require more reasoning now, I think there’s a trade off here, for example, they become arguably less natural, like especially referencing the natural question dataset of Google, they did a really good job of arguing that, you know, you should try to focus on questions people actually ask. And I’m sympathetic to that and that’s really wonderful that they could release those questions. But you know, I think we should also spend some time trying to figure out how to answer unnatural questions because people can do it and it stresses the systems in different ways. And now how do you know exactly what percentage and how to trade that off? I don’t have good answer, so I think you know, it’s, it’s still quite interesting either way.

Pradeep Dasigi

Can you say more about the distinction between those natural questions and unnatural questions,

Luke Zettlemoyer

Maybe I can make an analogy to semantic parsing. If you look at all the semantic parsing datasets like that, especially the real old ones like geo query and stuff, you know, the questions would be like what States border States that border States that border Texas or something. Right. And this is a beautiful sentence with lots of quantification in it, but you just can’t imagine someone ever actually asking that. But you know if I asked you too seriously and you had a map in front of you, know you could do the counting and you could draw the circles on the map or whatever and you can answer my question for me. Even if the questions are somewhat artificial and not things that people would normally ask, I’m still having systems be able to answer them. There’s value in that.

Matt Gardner

I guess the way I think about this and shameless plug, I put a paper on archive and I have another one coming that are very related to this. There are different reasons you might want to use question answering. One of them is to fill human information needs where like you, you really do want to target natural question distributions. You have something like a search box that people naturally type questions into. You want to answer these questions, this is great. But you might also use question answering to probe a systems understanding of something which is very much related to your QA SRL idea. And here it makes a less sense to talk about natural question distributions. I would say like there isn’t a natural distribution of reading comprehension questions. Why? Because if I have a paragraph in front of me, I just read it, I’m not gonna ask a question about it. That doesn’t really make any sense. People aren’t going to ask these questions naturally, but I can still ask arbitrary questions about that paragraph to probe either another person’s or a machine’s understanding of that paragraph. And these can be arbitrarily complex if I want to really probe, understanding.

Luke Zettlemoyer

I think that’s a really nicely stated. And that you can understand more about what the models can do by doing that in a probing sense. Another thing I would also highlight, just to add a little bit to that is that, you know, you can think of them also as an interface to end tasks. So like Omar Levy had a nice paper a few years back about doing relation extraction as question answering. And the idea is, you know, rather than making an expert that wants to extract certain relationships, right, regular expressions over dependency trees or whatever the state of the art might be, they can just, you know, say, Oh I want to know the manager at AI2 relation. So thing X that works for AI2 that has the property manager that’s, you know, but I only want Seattle so I’ll say you know, X lives in Seattle or something. Right. So whether it’s a little open IE tuples or whether it’s actually a formal questions, I don’t think it matters too much. But you sort of in English specify what structured is you’re looking for. And that hopefully is a friendlier interface than having to kind of understand the linguistics of what’s going on.

Matt Gardner

Yeah, definitely. Great. This has been really interesting. As a last topic, I think it’d be nice to come back to this contextualization idea in pre-training. How do you think the notion of getting data at scale with natural language annotations changes or fits into this idea of like we have these huge pre-trained language models and it still help?

Luke Zettlemoyer

I have to be honest and say when we were doing this, you know, this sort of notion of pre-training wasn’t even in my mind, but the deep learning was having a huge impact. Not as much in NLP as it is now, but you know everywhere else. And so literally I had in mind like, well if we could do QASRL maybe we can make an ImageNet, right? So imageNet is labeled, right? So my mindset at the time was that you’re going to have to get a huge label data set to get these big models to train in NLP. That was the mindset. And so it turns out that was, you know, wrong. It’s not a necessary condition. I mean sort of sometimes over lunch we’ll sit with my vision friends and then ask them like, well what would the ImageNet of NLP be like? These all the self supervised training enough or like what if we actually had a large label dataset?

Luke Zettlemoyer

What’s the analogy to where it works other places I would dream, you know in my wildest dreams QARSL could be a part of that. I don’t know if this is true, but I think it’s a fun thought exercise. You know, what is it that we don’t get from, you know, mass language modeling or the new generalizations of it in those things would be candidates for trying to label at scale or think of another proxy task. Maybe you’re lucky then you don’t have to label it. Maybe you can find data already. I think the field is already doing this a little bit with probing and so forth, but I think there could be a lot more of like really looking for tasks where things fail and trying to think about how to get that supervision as these models.

Matt Gardner

Yeah, that’s a good point. On the note of like what can and can’t you learn from language modeling or masks, language modeling. I’ve had a few Twitter conversations with Emily Bender and others about the linguistic theory of learning, meaning from form. And I guess linguists would tell you that if all I have is language modeling, there’s probably a lot that I’m missing. And maybe there’s room for getting more actual meaning by means of these additional annotations at scale.

Luke Zettlemoyer

I have to believe that’s true. Of course you could argue then you should go for, you know, cross modal and cross lingual. What we’re actually doing in our research is saying, you know, go bigger scale, go more cross lingual. We’re not doing multimodal personally, but I really am enjoying watching what other people are getting out of that. But at some point we’re going to hit a, you know, hit the ceiling of all that. And then I think, you know, hopefully with somebody who’s been thinking about, you know, what’s missing and what else we should be annotating. And you know, again, there’s all the interpretability angles and so forth too. It’d be really interesting to see how it goes. I’m still so hopeful that there’s some more leverage to be had here.

Matt Gardner

Have you been thinking about what’s missing? What else we could get?

Luke Zettlemoyer

No, I mean I don’t, I don’t have a good answer. I don’t think we understand. I’m actually been mostly trying to think about how to design experiments to figure out what’s missing rather than actually having any insight into what’s missing yet. I just think sadly everything is so new that that’s kind of where we are.

Matt Gardner

I agree,

Luke Zettlemoyer

But I hope that over the next few years we’ll make some real progress on that. I have a little worried that the underlying pre-training is changing so quickly that we might need to take a pause and see what, just kind of like probing the models now may not be relevant to the models that are going to be out in nine months or 12 months. I’m not sure and maybe may not be. It makes me a little nervous.

Matt Gardner

Going back to you mentioned Tom Dietterich’s post. A lot of people have thought about this for a long time. I guess what we really need is a set of unit tests in some sense for different capabilities. I think what we’re doing now with these probes and building datasets is, is trying to build unit tests. In some sense those tests will still be relevant no matter what the underlying models are.

Luke Zettlemoyer

Yeah, I totally agree. I’ve actually even encouraged very students to think about, you know, pick your favorite linguistic phenomenon, get your friends together, label a few hundred examples, whatever you can do an afternoon and you know, figure out like is it in there or not? And you know, if it is, then that’s kind of cool and that’s a finding and if it’s not, that’s kind of cool. It’s actually an opportunity to try to improve it and suddenly you’re doing science and not just engineering, like no matter the outcome. It’s kind of interesting.

Matt Gardner

I agree.

Luke Zettlemoyer

I think that would be a worthy goal. And you could imagine there’s a lot of those kinds of projects to be done.

Matt Gardner

Yup. It’s a great time to be an LP. Yeah. Cool. This has been a really interesting conversation. Was there anything that you wanted to cover that we missed or any final thoughts?

Luke Zettlemoyer

No, I’m just, you know, super excited I think it would be really interesting to see in the future, you know, how it all plays out with, you know, I’m sure there are plenty of people that believe that you shouldn’t be labeling lots of data anymore. I guess one thing I would say is, even if that’s true, you know, it’s still valuable to be able to label a little data real quickly in a new domain or in a new setting. So, you know, we’ve been mostly focusing on the big data setting here, but the small data setting is also quite interesting and arguably we should not forget that, but even there, you know, you’d like to be able to do it quickly, you’d like to be able to do with little training. So, so I think that in a sort of lots of avenues where you can take this whole direction.

Matt Gardner

Yeah. Great. Thanks Luke. This has been fun.

Luke Zettlemoyer

Thank you.

Pradeep Dasigi

Thanks Luke.