Method

For this classification we used as the main source the classification of tribes provided in Murdock (1969). In Murdock, each tribe is associated to a tribe number y within a chapter x so that its code is x:y. In most cases, the chapter is equivalent to a culture family encompassing a number of tribes.

As both Murdock and GREG geo-databases were manually recovered from historical maps, many measurement errors might exist due to the geo-referencing process. For instance: (i) polygons borders could be miss-located due to manual process, (ii) There must be complex geometries that cannot be intersect with other polygons, among others.

Establishing the reason why a specific geographical area is considered a homeland of two different tribes in Murdock and GREG is not always straightforward. We initially collect information from three main sources: (i) Wikipedia, (ii) eHRAF World Cultures , and (iii) country-specific books.