Atkinson on phoneme inventories in Science

[Frans Plank]

I wonder whether this is a minor or a serious question:  Just HOW does  
an individual, or a speech (sub)community, "lose" or "gain" "a  
phoneme"?  Well, linguistically speaking, it's about featural  
contrasts, really, and their syntagmatic incidence.   Could the  
answer(s) conceivably matter?  Or can historical/developmental  
phonology really be done without phonology?  But these are night  
thoughts.

Come to think of it, there have been few phonologists in this debate,  
so far.  They don't seem to be losing a night's sleep over the tale of  
the vanished African phonemes.

Frans


On Apr 20, 2011, at 10:39 PM, Matthew Dryer wrote:

> There are three problems that I am aware of with the Atkinson paper,  
> one minor, two serious.  My primary concern is the hypothesis that  
> there is a positive correlation between population size and size of  
> phoneme inventory.  Since his further "out-of-Africa" claims assumes  
> the former, it's not clear that he has anything interesting to say  
> about this if the former turns out to be false.
>
> First, he claims that phoneme inventories are relatively small in  
> North America.  Maddieson's WALS data does not provide data on  
> overall inventory size, only on consonant inventory, vowel  
> inventory, and complexity of tones.  Atkinson's way of deriving  
> overall inventory size is apparently to treat these three variables  
> equally.  However, this is not what is normally understood by  
> inventory size.
> Languages in North America tend to have large consonant inventories  
> and small vowel inventories, but large overall inventories since  
> large consonant inventory tends to lead to large overall inventory.   
> This is not as serious a problem as the next two, because if there  
> IS a correlation between population size and Atkinson's metric, then  
> that would be interesting.
>
> Second, in order to test any crosslinguistic hypothesis, one needs  
> to have a sample that is unbiased with respect to the phenomena  
> being examined.  In general, this is true for the WALS languages, as  
> long as one controls for genealogy and area.  But the WALS languages  
> are a highly biased sample as far as population size is concerned.   
> This is because there is a very strong correlation between  
> population size and availability of grammatical descriptions,  
> especially in Europe, Asia and Africa.  In fact, in constructing the  
> 200-language sample for WALS, we deliberately chose languages with  
> larger speaker populations in the sense that we deliberately chose  
> languages for which data was more readily available.  This bias  
> itself renders Atkinson's claims suspect, but his further claims  
> about distance from Africa are rendered further suspect since the  
> population bias in the sample is lower for languages further from  
> Africa.
>
> Third, although Atkinson controlled for non-independence within  
> families, he did not control for non-independence within areas and  
> because he failed to do so, his claims in terms of statistical  
> significance are invalid.  One of the goals of the WALS atlas is to  
> show areal patterns.  One has only to look at Maddieson's WALS map  
> for size of consonant inventories to see that there is a large area  
> in northwest North America with large consonant inventories (with  
> languages from many different families) and a similar area in  
> southeast Asia (again with languages from many different families)  
> and a large area in northern South America with small consonant  
> inventories (again with languages from many different language  
> families) and similarly for New Guinea.  In other words, size of  
> inventory can be an areal phenomenon.
>
> I have argued in many places that unless a correlation is found  
> independently in all parts of the world (in my method, the six  
> continental areas I use), then we cannot conclude that it is real.   
> Bill Croft says "I asked a couple of physicists with whom I  
> collaborate about what to think of global correlations when those  
> correlations are not found in most or all of the subpopulations that  
> the data may be partitioned into (areal, phylogenetic, etc.). They  
> both stated that a global correlation is statistically valid even if  
> the same correlation does not exist in all the partitioned  
> subpopulations."  But the big problem with the Atkinson paper and  
> others like it is precisely that nonlinguists who are experts on  
> statistics do not understand the peculiar nature of crosslinguistic  
> data.  It is obviously the case in general that correlations over a  
> domain can be valid even if they are not found in all subdomains.   
> But I argued in my 1989 paper on large linguistic areas that the  
> only way to determine whether there is a global correlation is see  
> whether it is true in all areas of the world.  This is actually  
> something of an overstatement; there are other ways to control for  
> areal factors.  But as a rule of thumb, if something is not found in  
> all areas or most areas, one should be very suspicious that the  
> apparent global correlation is simply an artifact of not controlling  
> for area.
>
> Bill's additional statement "One of them further added that another  
> possible reason is that the subpopulation samples may be too small  
> to provide a significant correlation one way or the other" also  
> betrays a lack of awareness on the part of these physicists of the  
> problem presented by areal phenomena.  With crosslinguistic  
> typological data, it is to all intents and purposes LOGICALLY  
> impossible to test for statistical significance WITHIN linguistic  
> areas because there are such strong areal patterns within large  
> areas that one cannot find enough independent cases to remotely  
> approach statistical significance.  We cannot, for example,  
> determine whether there is a correlation between population size and  
> phoneme inventory size within Africa on the basis of, say, three  
> languages.  But the areal patterns within Africa are such that one  
> cannot find more than three or so languages that are genealogically  
> and areally independent.  Linguists should be very wary of seeking  
> the advice of nonlinguists regarding statistics.
>
> Matthew
>
> Bill Croft wrote:
>> Atkinson argues for the existence of two correlations in a global  
>> sample of phoneme inventories: a correlation between size of  
>> phoneme inventory and distance from Africa, and a correlation  
>> between size of phoneme inventory and size of the population of the  
>> speech community. Atkinson needs the latter, phoneme-population  
>> correlation to justify his founder-effect explanation for the  
>> former correlation. The phoneme-population correlation was also  
>> identified by Hay and Bauer (2007). (Hay and Bauer also test  
>> Pericliev's [2004] data and found, pace Pericliev, that the  
>> correlation is also strong in his sample [Hay and Bauer 2007:397].)  
>> Johanna Nichols reports in her post a tentative result from her  
>> sample: she reports that the global correlation is present, but a  
>> division of the sample into large areas shows that the correlation  
>> does not exist, or is even negative, in some of the areas. On this  
>> basis, Johanna writes, "If there is really a correlation between  
>> population size and phoneme inventory size (or anything else), it  
>> should hold within areas as well as worldwide." She concludes that  
>> the global phoneme-population correlation is an artifact of  
>> population sizes in Eurasia and Africa, and areality in Africa plus  
>> neighboring regions.
>> Interestingly, with Dunn et al., the shoe is on the other foot with  
>> respect to global correlations and correlations in subpopulations.  
>> Here it is Dunn et al. who argue against the global word-order  
>> correlations manifested in Greenbergian word order universals. Dunn  
>> et al. argue that a correlation between various pairs of word  
>> orders are supported in some language families but not others.  
>> Hence word-order correlations are lineage-specific (and culture- 
>> specific) rather than universal in the Greenbergian sense. Dunn et  
>> al. divide the global sample into phylogenetic subpopulations  
>> rather than areal subpopulations, but the point is the same. (There  
>> are two differences between Dunn et al.'s analysis and the  
>> Greenberg universals: the Greenberg universals are synchronic,  
>> while Dunn et al's data is a sample of diachronic word order  
>> changes; and the model that Dunn et al. tests is not the model  
>> implied by Greenbergian universals. While these differences are  
>> important, as I argued in my post on their paper, I believe they  
>> aren't relevant to the point being made here.) And in the case of  
>> Dunn et al., Matthew Dryer argued in a post that the lineage- 
>> specific correlations are random effects and the globally  
>> identified Greenbergian word-order correlations are real.
>> I asked a couple of physicists with whom I collaborate about what  
>> to think of global correlations when those correlations are not  
>> found in most or all of the subpopulations that the data may be  
>> partitioned into (areal, phylogenetic, etc.). They both stated that  
>> a global correlation is statistically valid even if the same  
>> correlation does not exist in all the partitioned subpopulations.  
>> This situation may arise when negative correlations or  
>> noncorrelations in some subpopulations are more than compensated  
>> for by positive correlations in other subpopulations, so that the  
>> global effect is a positive correlation. (One of them further added  
>> that another possible reason is that the subpopulation samples may  
>> be too small to provide a significant correlation one way or the  
>> other.) When pressed further about why a global correlation would  
>> not lead to the same correlations in (large enough) subpopulations,  
>> the response was that, in the simplest case, X is dependent not  
>> only on Y but also on a factor Z that varies considerably from  
>> subpopulation to subpopulation; and that one would expect the same  
>> correlations in the subpopulations if and only if most of the  
>> observed variation in X is due to Y. In fact, this is not the case  
>> for the phoneme-population correlation: Atkinson shows that  
>> language family membership, which clearly varies by region,  
>> accounts for the greatest amount of variance for phoneme inventory  
>> size. But the other correlations still hold globally when combined  
>> with this factor (Atkinson, supplementary materials, pp. 5-6). So  
>> it appears that the global phoneme-population and word-order  
>> correlations are valid, that is, there is a factor (or factors) Y  
>> that needs to be accounted for; but there is apparently also a  
>> factor or factors Z that lead to areal- and/or phylogeny-specific  
>> differences in the linguistic patterns.
>> Of course, correlation is not causation, as we all know. We have to  
>> find an explanatory framework that allows us to say that when X  
>> correlates with Y (and Z), there is a causal connection between X  
>> and Y (and Z). One problem with the global phoneme-population  
>> correlation is that there is no satisfactory explanation for it:  
>> even the linguists who found the correlation have only a few  
>> suggestions that they do not consider to be strong enough to offer  
>> as an explanation. Conversely, there is no obvious explanation why  
>> word-order correlations might be lineage- or culture-specific. For  
>> example, no cultural reason easily comes to mind why Proto-Indo- 
>> Europeans and their descendants couple verb-object and adposition- 
>> noun order, but Proto-Uto-Aztecans and their descendants do not.  
>> Nor is there an obvious culture-specific nonlinguistic behavior  
>> that might be causally connected to word-order patterns in the way  
>> that spatial cognition has been shown to be connected to linguistic  
>> spatial frames of reference by Levinson and his colleagues.
>> Bill
>> Hay, Jennifer and Laurie Bauer. 2007. Phoneme inventory size and  
>> population size. Language 83.388-400.
>> Pericliev, Vladimir. 2004. There is no correlation between the size  
>> of a community speaking a language and the size of the phonological  
>> inventory of that language. Linguistic Typology 8.376-83.