A/B Testing Interview
Design, size and read out experiments. Cover power, peeking, guardrails, interference and what to do when results disagree.
Skills covered: Experiment design · Power and MDE · Guardrails · Readouts · Multiple testing · Confidence intervals
Start the free diagnosticNo account is needed for free questions.
01
Free diagnostic
One question to find where you stand.
02
30-minute practice
Free questions that fit in half an hour.
- Why peeking inflates false positivesQuick check · Readout · 5 min · EasyFree
- Big week-1 lift that fades to zeroQuick check · Readout · 5 min · EasyFree
- Type I vs Type II error trade-offQuick check · Intervals · 5 min · EasyFree
- The returning-planes problemQuick check · Bias · 5 min · EasyFree
- When the mean misleadsQuick check · Descriptive stats · 5 min · EasyFree
03
3-day plan
Two questions a day, easier first.
Day 1
Day 2
Day 3
04
7-day plan
Two questions a day, easier first.
Day 1
Day 2
Day 3
Day 4
Day 5
Day 6
Day 7
05
Final timed simulation
Answer under interview conditions: no hints, one sitting.
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