A linguistic area is" a geographical region in which neighboring languages belonging to different language families show a significant set of structural properties in common, where the commonalities in structure are due to historical contact between speakers of the languages, and where the shared structural properties are not found in languages immediately outside the area (ideally where these include languages belonging to the same families as those spoken inside the area)"(Enfield 2005: 190). That is, a linguistic area is defined by a group of variables (henceforth we use this term rather than features, properties, etc.) each of which constitutes an isogloss demarcating the area. Some linguists seek variables that form an isogloss bundle (eg Campbell et al. 1986, Joseph 1983, 2001); others do not (eg Emeneau 1956, Masica 1976), but nonetheless implicitly assume that some core part of the area should ideally emerge as located inside of all the isoglosses. Some works seek isopleths rather than isoglosses (van der Auwera 1998) and rank languages for the number of areal features they share. All of these approaches assume what we will call categoriality in the distribution of the defining variables: some value of a variable is present inside the area and absent outside of it (that is, in the neighboring languages outside of it). Variable-defined areas present various problems. First, there are no criteria for deciding which are the diagnostic variables. This problem has an empirical side: the linguist needs to determine which variables are more and less frequent worldwide, which ones are most and least likely to diffuse, to be inherited; etc. It also has a statistical side. Suppose the linguist sorts through 200 variables and finds five that appear to be area-defining. Is this a significant result, or could one expect to find five out of 200 shared variables for any random set of languages and any random set of variables? The isogloss-bundled areal features standardly accepted for the Balkan and Mesoamerican language areas are selected from the entirety of the sound system, inventory of morphological forms, and basic syntactic inventory, a total set of elements that must number at least 200 and appears to be openended in practice. Half a dozen out of 200, or even 100, surveyed variables could easily cooccur in some set of languages by chance if they were at all frequent;