input vs. network effects in the multiagent modeling of morphological leveling in old castilian...

Input vs. network effects in the multiagent modeling of

morphological leveling in Old Castilian

Harry Howard

Tulane University

LASSO 2006Laredo, TX

LASSO 2006 Harry Howard 2

Tuten (2003) on koineization in the history of Spanish By the 11th century, (southern) Castilian differed strikingly from its Romance neighbors in the simplicity of its definite articles

Castilian had almost reached its modern analyticity, with no allomorphs of the plural forms and only two preposition + article contractions (al, del).

The only difference was allomorphy in the singular forms (el-elo; la-ela-l). In contrast, the other Ibero-Romance dialects were considerably more complicated, with multiple article allomorphs, as well as contractions onto the prepositions por, de, a, con, and en.


Koineization Tuten attributes the simplicity of Castilian to koineization, and in particular to a process of dialect leveling that occurs when speakers leave established, monodialectal social networks whose members are bound together by strong ties and move into new, polydialectal social networks whose members are bound together only weakly.

In the particular case of 11th century Castilian, Tuten see the initial stages of the Reconquest and the establishment of Burgos as the capital of its leading edge as supplying the conditions for the latter kind of society.


Our response Tuten’s updating of a classic problem in Romance linguistics, conflates two causal factors, how language is learned in situations of multiple competing inputs (i.e. dialect mixing)

how language is learned in situations of social innovation (i.e. weak social networks).

Of course, there are no longer any native speakers of 11th century Castilian to interview, so Tuten cannot be faulted too harshly for not disentangling his causal factors more carefully.


Our approach In fact, the lack of real native speakers means that the best we can do is construct artificial ones, via computer programs, and see how they behave as parameters are varied.

This brings us to the realm of multiagent modeling, which has recently seen a burst of enthusiasm in the creation of sociolinguistic microcosms for the simulation of language evolution.

De Boer’s (2001) investigation of the evolution of vowel systems provides a convenient starting point.


Table 1. Definite article allomorphs in Galicia & Portugal

no art. -- por de a con en Masc sg o, lo polo, pelo do, du ao, au, ó co no Fem sg a, la pola, pela da aa, á cia na Masc pl os, los polos, pelos dos, dus aos, ous, ós cos nos Fem pl as, las polas, pelas das aas, ás coas nas


The Western Mediterranean in 1030


The algorithm1. an agent chooses a meaning from its semantic memory.

In our simulations, this will be an unexpressed noun with features for gender and number, plus a preceding context, either one of the five prepositions or not.

2. the phonemic representation of the meaning is retrieved from memory, converted to phonetic form, and ‘spoken’ to another agent, which

3. matches it to its phonemic memory, in order to 4. retrieve a meaning which 5. it tries to match against the meaning intended by the

speaking agent. If there is a match, 6. the hearing agent stores the phonemic-semantic

association.


Table 2. Vectors for the gender and number features of Ibero-Romance nouns

Masc Fem Sg [1 1] [-1 1] Pl [1 -1] [-1 -1]


Table 3. Vectors for Ibero-Romance free and prepositional contexts of article allomorphs

free 0 0 0 0 0 por 1 0 0 0 0 de 0 1 0 0 0 a 0 0 1 0 0

con 0 0 0 1 0 en 0 0 0 0 1


(1) Phonemes for Ibero-Romance definite article allomorphs

vowels: /(i), e, a, o, u/ consonants: /k, d, s, n, l, r, p/


(2) Hubey’s (1999) three dimensional phase space of acoustic-articulatory events

x) stricture quality, the area (length*width) of a stricture multiplied by its characteristic frequency ω measured in radians/sec = l*w*ω.

y) stricture change, the time derivative of the change in stricture area = d/dt (l*w)*ω.

z) quasi-Reynold’s number, found by multiplying the characteristic length (K) by velocity (v = l /time) = K*v.


(4) Hubey’s approximations x) stricture quality = {{k,g,x,h}, r, {l,s,z}, {d,t,}, {f,v}, {p,b,m}}

y) stricture change = {{vowels}, {dipthongs}, {r,l,m.n,s,f,,x,h}, {b,d,g}, {p,t,k}}

z) Reynold’s number = {{vowels, dipthongs}, {r,l,m,n}, {v,z}, {s,f,,x,h}}


Table 4. Phonemic vectors for the Ibero-Romance definite article allomorphs

u o a e k d s n l r p X .1 .2 .5 .7 .1 .6 .7 .7 .7 .7 1 Y 0 0 0 0 1 .5 .1 .1 .2 .2 1 Z .1 .1 .1 .1 1 .5 .9 .2 .2 .2 1


Table 5. Word matrix for Galician-Portuguese pola

p o l a X 1 .2 .7 .5 Y 1 0 .2 0 Z 1 .1 .2 .1


Figure 1. Fifteen [l], made by adding noise with mean 0 and standard deviation 1 to /l/


Figure 2. Frequency of Galician-Portuguese morphemes idealized at 1:3:5


Figure 3. Development of Galician-Portuguese morpheme categories towards 1:3:5


Figure 4. Imperfect development of Galician-Portuguese morpheme categories


Production A simple algorithm for leveling the preposition-article contractions: Use more frequent forms over less frequent ones

Note that the less frequent forms will be even less frequent in the environment of 13th century Castilian, since there were also competing forms from Leonese, and Aragonese, as well as Northern Castile


The social model It appears that strong ties/dense social networks are necessary to maintain less frequent forms, but it could also be that such societies are more isolated or less porous to outsiders

input vs. network effects in the multiagent modeling of morphological leveling in old castilian...

Documents