My core interest is the worldwide distribution of linguistic diversity (a field known as ‘language typology’). This involves the development of variables that allow measuring diversity, the formulation of theories explaining the distribution of these variables, and the study of the relationships of linguistic distributions to (biological) genetic diversity as well as to cultural and cognitive diversity. The methods used in this research range from the statistical analysis of typological databases and corpora to ethnolinguistic fieldwork and experimental methods.
Current foci of research include the typological profile of Eurasia; the analysis of cross-linguistic variation in the domains of grammatical relations and morphology as well the impact of this variation on discourse style, language acquisition, and language processing; and the development of new methods for measuring and testing universal and areal distributions and their historical developments. Recently I have also started collaboration with anthropologists and biologists on the evolution of language, taking a broad comparative approach.
I am co-director (with Johanna Nichols at UC Berkeley) of the AUTOTYP research program for typological databasing and have been leading a series of fieldwork projects on typological outlier languages in the Himalayas (e.g. on the Chintang language).