Chatomics Field GuideWhat They Don't Teach You

Topic

Normalization choice

Which normalization is right for my question, and which ones must never be mixed?

Library-size normalization assumes most genes do not change; that assumption fails for global shifts, cell-type composition changes and spike-in designs. Median-of-ratios, TMM, CPM, TPM and SCTransform answer different questions and are not interchangeable inputs to downstream tools.