Sampling bias
Survivorship, self-selection and non-response — the three that account for most confidently wrong business numbers.
Identify who is missing from a dataset and say which direction their absence pushes the result
Up to 3 questions on this skill alone, marked against the bar beside this. It stops as soon as the answer is clear. No account, and your answers are not kept.
You'll need these first
What it unlocks
Start on Statistics & Data Literacy
Every skill above, ordered by what depends on what, with the projects above that as the evidence you actually did it. We work out where you already are first, so the path skips what you can do.
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