Questions / Quant research, Data & feature research
An average of averages
Group A has 2 observations with mean 10. Group B has 8 observations with mean 20. What is the pooled mean?
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Answer: 18 units
- The pooled mean is (2×10 + 8×20)/10 = 18.
Interview shortcut. Weight group means by counts: (2 × 10 + 8 × 20)/10.
In the app this has a follow-up where one thing about the setup changes. Try the follow-up.