In the GramAdapt project we have tailored each piece of the research design so that the model of causation, approach to comparison, sampling, variable selection, and statistical inferences would be compatible with one another (publ. 10, 19). A review and synthesis of causes of language change has been used in developing other parts of the design, informed by collaborative work on the evaluation of causal chains in language evolution (publ. 2). For selecting languages and communities, we have developed and tested a new sampling method that builds on our earlier work but is sensitive to the relationship of languages in contact unlike previous techniques (publ. 6, 13, 17). The sampling method is a crucial part of a typological method that we have developed for identifying linguistic outcomes of language contact which lets us assess the probability of contact-induced language change in a Bayesian way (publ. 19). The method has been validated with Bayesian ancestral state reconstructions, principal component analysis, and by comparing inferences based on our data to those drawn from more qualitative research on outcomes of language contact (publ. 17; dissem. 12; Di Garbo & Kapellis, in revision). Based on the approach we have analyzed linguistic data on five broad linguistic domains in 150 languages and the data will be made openly accessible upon the publication of a release paper in preparation. The selection of linguistic variables for typological comparison has been informed by pilot analyses (publ. 4, 8, 11, 12, 16, 18).
The most innovative aspect of the project has been developing methods for combining sociolinguistic and typological approaches to language variation. We have developed a questionnaire and comparative parameters for researching sociolinguistic ecology that have guided and structured our data collection (Kashima et al., accepted; Sinnemäki & Kashima, in prep.). The questionnaire is informed by insights from our earlier work (publ. 2, 5, 12) and its design incorporates knowledge from language processing, language acquisition, language socialization, linguistic anthropology, and sociolinguistics. We have also reviewed research in sociolinguistic typology as well as comparative research in variationist sociolinguistics (Sinnemäki, in revision; Sinnemäki & Kashima, in revision). Sociolinguistic data has been collected in collaboration with roughly 50 experts worldwide and the first version of the dataset has been published (Open data 5). About half of the experts (e.g. Kashima & Schokkin, accepted) also contributed a chapter on the bilingual language ecology to a collection of articles edited by members of the research team (Di Garbo, Kashima & Sinnemäki, forthcoming). Based on our approach and data we have also argued how typological research could be methodologically renewed on a wider scale (Di Garbo et al., in review).
The initial results on testing hypotheses about linguistic adaptation suggest at least partial evidence for adaptations but also correctives to earlier research (publ. 5, 12, 18; dissem. 8, 9, 10; see below).
Selected publications:
Di Garbo, F., E. Kashima & K. Sinnemäki (eds.) (forthcoming). Social Foundations of Language Contact: A Comparative Survey. Language Science Press.
Di Garbo, F. & P. Kapellis (in revision). Contact effects in nominal number systems: A worldwide survey. Studies in Language.
Di Garbo, F. et al. (in review). Towards greater social anchoring in language typology. Linguistic Typology at the Crossroads.
Kashima, E. et al. (accepted). The design principles of a sociolinguistic-typological questionnaire for language contact research. Language Dynamics and Change.
Kashima, E. & D. Schokkin (accepted). Nen and Idi Social Contact, Southern New Guinea. In F. Di Garbo et al., Social foundations of Language Contact: A Comparative Survey. Language Science Press.
Sinnemäki, K. & E. Kashima (in revision). Language typology and variationist sociolinguistics. An invited chapter in Y. Asahi et al. (eds.), Routledge Handbook of Variationist Sociolinguistics. Routledge.
Sinnemäki, K. & E. Kashima (in prep.). Comparative historical sociolinguistics. An invited chapter to B. Drinka et al. (eds.), Handbook of Historical Sociolinguistics. Mouton de Gruyter.
Sinnemäki, K. (in revision). On the "socio" in sociolinguistic typology: A review. Linguistics.