Paper 2 · Statistics
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Lesson 14 of 21
Statistics 14 z scores 6 (standardising sample means)
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- Standardise a sample mean with z = (x̄ − μ)/(σ/√n) instead of σ
- Spot the 'sample of n … average' wording that signals dividing by √n
- Explain why sample means cluster tighter than individuals (standard error σ/√n)
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