f4-statistics explained: the arithmetic under every ancient-DNA claim
f2, f3, f4 and D-statistics are the shared-drift arithmetic beneath qpAdm, qpWave and admixture graphs. What each statistic measures, how a four-population test works, and how to read Z-scores like the papers do.
Related posts
qpWave explained: counting ancestry streams before naming them
qpAdm's sibling asks a prior question — how many independent streams of ancestry does a set of populations need? The rank test, cladality checks, and why every good qpAdm search starts with a qpWave answer.
3 min read
Every number in your qpAdm report: the model record explained
What the full qpAdm model record in an Ancestrify report means — chi-square, degrees of freedom, f4 rank, SNP counts, jackknife blocks, 95% confidence intervals, the nested-model table and the rank test — and how to read the plain-text download.
11 min read
How to read qpAdm results: p-value, Z-score and SE
A plain reading guide to the three numbers in every qpAdm result — what the p-value tests, what a standard error bounds, what a Z-score rules out — with worked examples and the mistakes that make a passing model wrong.
6 min read