Africa map (and claim) of the day

. . . [O]ur result provides large-scale formal econometric evidence in support of the African historiography that emphasizes the importance of ethnic institutions and other historical features in shaping economic performance suggesting that research on African development needs to focus at the ethnicity rather than the country level.

That is from a paper by Michalopoulos and Papaioannou (June 2011).

From the abstract:

. . . [D]ifferences in countrywide institutional arrangements across the border do not explain differences in economic performance within ethnic groups. In contrast, we document a strong association between pre-colonial ethnic institutional traits and contemporary regional development.

It seems that a new version of the paper (July 2012) has a different title (see here).  

The paper contributes to the body of literature on the historical reasons for contemporary economic performance. The literature review in the paper is well developed.