Category: Language

The different functions of probabilty in probabilistic grammar

I have long been critical of naïve interpretations of probabilistic grammar.  To me, it seems like the major motivation for this approach derives from a naïve—I’d say overly naïve—linking hypothesis mapping between acceptability judgments and grammaticality, as seen in Likert scale-style acceptability tasks. (See chapter 2 of my dissertation for a concrete argument against this.) But in this approach, the probabilities are measures of wellformedness.

It occurs to me that there are a number of ontologically distinct interpretations of grammatical probabilities of the sort produced by “maxent”, i.e., logistic regression models.

For instance, at M100 this weekend, I heard Bruce Hayes talk about another use of maximum entropy models: scansion. In poetic meters, there is variation in, say, whether the caesura is masculine (after a stressed syllable) or feminine (after an unstressed syllable), and the probabilities reflect that.1 However, I don’t think it makes sense to equate this with grammaticality, since we are talking about variation in highly self-conscious linguistic artifacts here and there is no reason to think one style of caesura is more grammatical than the other.2

And of course there is a third interpretation, in which the probabilities are production probabilities, representing actual variation in production, within a speaker or across multiple speakers.

It is not obvious to me that these facts all ought to be modeled the same way, yet the maxent community seems comfortable assuming a single cognitive model to cover all three scenarios. To state the obvious, it makes no sense for a cognitive model to acconut for interspeaker variation because there is no such thing as “interspeaker cognition”, there are just individual mental grammars.

Endnotes

  1. This is a fabricated example because Hayes and colleagues mostly study English meter—something I know nothing about—whereas I’m interested in Latin poetry. I imagine English poetry has caesurae too but I’ve given it no thought yet.
  2. I am not trying to say that we can’t study grammar with poetry. Separately, I note, as did, I think, Paul Kiparsky at the talk, that this model also assumes that the input text the poet is trying to fit to the meter has no role to play in constraining what happens.

Use the minus sign for feature specifications

LaTeX has a dizzying number of options for different types of horizontal dash. The following are available:

  • A single - is a short dash appropriate for hyphenated compounds (like encoder-decoder).
  • A single dash in math mode,$-$, is a longer minus sign
  • A double -- is a longer “en-dash” appropriate for numerical ranges (like 3-5).
  • A triple --- is a long “em-dash” appropriate for interjections (like this—no, I mean like that).

My plea to linguists is to actually use math mode and the minus sign when they are writing binary features. If you want to turn this into a simple macro, you can please the following in your preamble:

\newcommand{feature}[2]{\ensuremath{#1}\textsc{#2}}

and then write \feature{-}{Back} for nicely formatted feature specifications.

Note that this issue has an exact parallel in Word and other WYSIWYG setups: there the issue is as simple as selecting the Unicode minus sign (U+2212) from the inventory of special characters (or just googling “Unicode minus sign” and copying and pasting what you find). 

On alternative frameworks

[continuing an argument from earlier…]

I think that intellectual diversity and academic freedom are good baseline values, but that they are not so obviously a positive value in pedagogy. Students genuinely look to their instructors for information about approaches to pursue, and not all frameworks (etc.) are of equal value. Let us suppose that I subscribe to theory P and you to theory Q (≠ P). Necessarily one of the following must be true:

(1) P and Q are mere notational variants (i.e., weakly equivalent or better).
(2) P is “more right” than Q or Q is “more right” than P.

In the case of (1), the best pedagogical practice would probably be to continue to propagate whichever of {P, Q} is more widely used, more intellectually robust, etc. For instance if Q is the more robust tradition, efforts to “port” insights and technologies from Q to P contribute little, and often quite difficult in practice. Of course this doesn’t mean that P and its practitioners should be suppressed or anything of the sort, but there is no strong imperative to transmit P to young scholars.

In the case of (2), the best practice is also to focus pedagogy on whichever of the two is “more right”. Of course it is often useful to teach the intellectual history, and it is not always clear which theory is out ahead, but it is imperative to make sure students are conversant in the most promising approaches.

In the case of computational syntactic formalisms, weak equivalences hold between minimalist grammars (MGs) as formalized by Stabler and colleagues) and most of the so-called alternative formalisms. It is also quite clear to me that insights largely flow from minimalism and friends (broadly construed) to the alternative formalisms, and not the other way around. Finally, efforts to “port” these insights to alternative formalisms have stalled, or perhaps are just many years behind the bleeding edge in syntactic theory. (1) therefore applies, and I simply don’t see the strong imperative to teach the alternative formalisms.

In the case of computational phonology, there is also an emerging consensus that harmonic grammar (HG) of the sort learned by “maxent” technologies) have substantial pathologies compared to earlier formalisms, so that classic Optimality Theory (OT) is clearly “less wrong”. I am similarly sympathetic to arguments that global evaluation frameworks including HG and OT are overly constrained with respect to opacity phenomena and overgenerate in other dimensions, and these issues of expressivity are not shared with imperative (i.e., rule-based) and declarative (i.e., “weakly deterministic” formalisms of the “Delaware school”). (2) thus applies here.

Of course I am not advocating for restrictions on academic freedom or speech in general; I make this argument only regarding best pedagogical practices, and I’m not sure I’m in the right here.

Trust me, I’m a linguist

Grice’s maxim of quantity requires that one give no more information than is strictly required. This is somestimes misunderstood as a firm constraint, but one intuition you may have—and which is nicely expressed by rational speech act theory—is that apparent violations of this maxim by an otherwise cooperative speaker may actually tell you that seemingly-irrelevant information is, in the mind of the speaker, of great relevance to the discourse.

I recently read two interviews in which the subject—crucially, not a working linguist—drew attention to their linguistics education.

The first is this excellent profile of Joss Sackler, a woman who married into the Sackler opioid fortune. To be fair, she does hold a PhD in Hispanic & Luso-Brazilian literatures & languages (dissertation here), which ought to qualify one, but her response to the Town & Country reporter asking some bad press is exactly the kind of non-sequitur a rational speaker ought not to make: “They’re going to regret fucking with a linguist. They already do.”

The second comes from interviews with Nicole Daedone, the co-founder of an organization (it’s hard to describe, just read about it if you’re interested) called OneTaste. I’ve now read several profiles of her (the first was in the New York Times, I think, years ago, but I can’t find it anymore), and in each they mention that she studied linguistics in San  Francisco; one source says she has a bachelor’s degree in “gender communications and semantics” from San Francisco State University, another says she was at some point working on a linguistics PhD there. The relevance was again unclear to me, but later I read the very interesting book Future Sex, which also profiles her. There, there is a brief discussion of the lexical semantics of pussy; Daedone, who is (it’s complicated) a sex educator, proposes that it fills a lexical lacuna, by providing a single term that refers to the human vulva and vagina as a whole.

This all makes me wonder whether to the general public, linguistics really connotes brilliance, and, perhaps, tenacity. And it makes me wonder whether one could actually wield their linguistics education as a shield against criticisms having nothing to do with language per se.

ACL Rolling Reviews don’t roll anymore

Recently I wanted to submit a paper to the ACL’s rolling reviews system. The idea of this system is that instead of people rushing to make somewhat arbitrary conference deadlines—most everything is published at conferences rather than books or journals in NLP—one can instead submit to an ever-running pool of reviewers and get quick comments. Furthermore, the preprints are available online and one can see the comments. After you the author feel that you’ve received a satisfactory review you can then “submit”, with the push of a button, your already-reviewed paper to a conference and the organizers and area chairs put together a program from these papers. This seems like a good idea thus far, even if the very strong COI policy means that none of the papers I get assigned to review are interesting to me but rather in adjacent (and boring) areas.

I was recently surprised to find—it’s not documented anywhere, I had to write tech support and wait to hear back—that it there are now blackout periods of several weeks where one cannot submit. I have no idea why this is true. Granted, they reduced the frequency of the cycles to six a year (or one every two months), but I don’t understand why I can’t, on July 1st, submit to the August 15th cycle. This makes no sense to me and seems to defeat the most important part of this initiative: the idea that you can submit work when it’s done rather than when certain stars align.

Myths about writing systems

In collaboration with Richard Sproat, I just published a short position paper on “myths about writing systems” in NLP to appear in the proceedings for CAWL, the ACL Workshop on Computation and Writing Systems. I think it will be most of all useful to reviewers and editors who need a resource to combat nonsense like Persian is a right-to-left language and want to suggest a correction. Take a look here.

Defectivity in Scottish Gaelic

[This is part of a series of defectivity case studies. Hat tip to John Hutchinson for this valuable information.]

I am currently wrapping up a class at the LSA Institute class on defectivity, and as part of this class students presented case studies. Some of them students enriched case studies I have already presented in this defectivity blog series; the following new-to-me case was provided to us by John Hutchinson of the University of Surrey.

Defective verbs in Gaelic have been long noted, particularly by Dwelly (1911) and Maclaren (1935). They are something of a grab-bag. First, there are verbs with tense restrictions:

  • The verb of quotation ars/orsa ‘said’ is restricted to past tense only.
  • Where English has the adverb almost, Gaelic has theab, which selects a verb-noun complement (e.g., theab e fhéin a bhith marbh ‘he was almost dead’) and which is also restricted to past tense.
  • The verb faod ‘may’ is non-past only.
  • The verb feum ‘must’ is non-past only, though Hutchinson notes that past forms do occur in corpora.

There are also a number of verbs which occur only in the imperative (cf. my judgments about English beware):

  • trothad/trobhad ‘come here’
  • t(h)iugainn ‘come along’
  • thalla ‘go away’
  • siuthad ‘go on, fire away’
  • feuch ‘behold’ (though note this is not defective in the sense of ‘show’)

Finally, Hutchinson notes that prepositions are inflected for person and number but eadar ‘between’ (naturally enough) only has plural forms. These cases of defectivity make a lot of semantic sense to me, particularly the restriction on the modal-like verbs and on ‘between’.

References

Dwelly, E. 1911. Illustrated Gaelic English Dictionary. Alex Maclaren & Sons.
Maclaren, J. 1935. Maclaren’s Gaelic Self-Taught, 4th edition. Alex Maclaren & Sons.

Defectivity in French

[This is part of a series of defectivity case studies.]

Morin (1987:33f.), cited in Boyé & Cabredo Hofherr (2010), draws attention to the French verb frire ‘to fry’. It is unobjectionable in the present active singular—je fris, tu fris, il frit—but apparently defective in the plural; according to my informants, speakers paraphrase this using inflected forms of faire frire ‘to make fried’. Arrivé (1987), also cited by Boyé & Cabredo Hofherr, lists frire and about a dozen other verbs as defective; according to my informants, all are rare, archaic, or unfamiliar.

Consider the case of frire briefly. It has an obvious analogical model: rire ‘to laugh’, which suggests *nous frions ‘we fry’, and so on. One obvious possibility is that this is somehow in competition with *nous frissons (cf. je finis/nous finissons ‘I/we finish’ and most 2nd conjugation verbs), which would give rise to a weird homophony with the plural of frisson ‘shiver; excitement’.1

Endnotes

  1. Here the ss appearing in the plural is ultimately descended from the Latin inchoative infix -sc- as seen in, e.g., nascō ‘I am born’. Neat, right?

References

Arrivé, M. 1997. La conjugaison pour tous. Hatier.
Boyé, G., and Cabredo Hofherr, P. 2010. Defectivity as stem suppletion in French and Spanish verbs. In Defective Paradigms: Missing Forms and What They Tell Us, ed. M. Baerman, G. G. Corbett, and D. Brown, 35–52. Oxford University Press.
Morin, Y.-C. 1987. Remarques sur l’organisation de la flexion des verbes français. ITL Review of Applied Linguistics 77-78: 13-91.

“Hi both”

I recently noticed that I have been receiving emails, addressed to multiple recipients, with the salutation

Hi both,

In fact I appear to have 34 of them in one of my many inboxes, including two received from different authors today. For me, this is sharply ungrammatical, though I am not sure why. Both is unobjectionable in subject or object position (e.g.,  Both liked limoncello, She fancies both, etc.) so I am not sure why it is bad in a salutation. A very informal survey of the people who have sent it to me shows two speakers for whom English is their second language (though both have extremely high proficiency) but also several native speakers too. Any ideas?