Nilotic (Tanzania) admixture calculator

The Nilotic (Tanzania) calculator is a curated Global25 source panel: 3 reference populations from the Classical Antiquity era, each entering the model as one composed coordinate row. It was curated for one scope, Tanzania · Maasai (Tanzania), so its sources are chosen to be informative for that ancestry rather than for everyone. The fit itself is a Monte-Carlo search in the nMonte tradition: weight is distributed across these sources until the weighted mixture sits as close to your pasted coordinate as it can get, and the leftover gap is reported as the fit distance.

Era scoping is what makes the panel meaningful. Every source here is a Classical Antiquity population, so the percentages read as "which of these Classical Antiquity groups does my coordinate resolve into", not as a family tree and not as a statement about any other period. The same coordinate run against a different era's panel will legitimately return a different breakdown, because the question changed.

The limit to keep in view: a coordinate fit cannot reject a model. It will return percentages from this panel even if none of these populations is genuinely ancestral to you, and the fit distance is the only signal that the answer is strained. Sources that sit close together in the reference space also trade weight almost freely, so treat small differences between neighbouring sources as noise. For a method with a p-value that can test a model and refuse it, see Ancient Ancestry, our qpAdm analysis.

Reading the fit itself: on a curated panel of this size, a scaled fit distance at or under about 0.020 is excellent, roughly 0.020 to 0.035 is the ordinary range for real individuals, and past about 0.045 either a relevant source is missing or your coordinate is not well described by this era's populations. Two cautions travel with those bands. A fit from this panel is never comparable with a fit from a panel of a different size, because adding sources always lowers the number whether or not they belong. And a nearest-population distance beyond roughly 0.08 anywhere on this site usually means an unscaled or damaged paste rather than unusual ancestry.