simona-degiorgi/northern-nigeria-language-mapping

Four thematic maps of household language use in northern Nigeria, from open REACH/ClearGlobal survey data. Python + QGIS. # Main household language in northern Nigeria Four thematic maps of language use across 131 Local Government Areas (LGAs) in six northern Nigerian states, built from open humanitarian survey data. Data preparation and quality checks in Python; cartography in QGIS. ## What the data measures The underlying survey question is: > *What is the main language your household uses at home?* It is a **single-response** question, the unit is the **household**, and it refers to the **main** language at home. So the mapped values are the share of households reporting a given language as their main one — **not** the share of speakers. The distinction matters: Hausa is widely used as a lingua franca across northern Nigeria by people who speak something else at home, so actual speakers are considerably more numerous than these maps suggest. --- ## The maps ### 1. Survey coverage Where the data exists. The dataset covers 131 of the 774 LGAs, in six states. Five LGAs in northern Borno are missing because the survey could not reach them. ### 2. Prevalent language by LGA The most frequently reported main household language in each LGA. Eleven distinct languages; Hausa prevails in 91 of the 131 LGAs. ### 3. Spread of Hausa Hausa appears in 130 of 131 LGAs, but is the prevailing language in only 91. The single LGA without it — Kala/Balge, on the Cameroon border — is a genuine absence, not a data gap: it is a Kanuri and Shuwa Arabic area. Class breaks are user-defined. The distribution is heavily skewed — median 0.88, third quartile 0.99 — so the top of the range is split more finely (0.75–0.95 and 0.95–1) to separate LGAs where Hausa is dominant from those where it is close to universal. The breaks are deliberately kept round and interpretable so that maps of different languages remain comparable. ### 4. Language composition of the north-eastern states Pie charts for Adamawa, Borno and Yobe. Only the north-east is shown — see below for why. --- ## The method …