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Compatibility function
CONFIDENCE
Returns the confidence interval for a population mean using a normal distribution; replaced by CONFIDENCE.NORM.
Rarely usedDifficulty 1400 · AdvancedUsage rank #390 of 520
When to use it
The confidence interval half-width using the normal distribution. Replaced by CONFIDENCE.NORM.
The shape of it
- Syntax
=CONFIDENCE(alpha, standard_dev, size)
Worked examples
95%
=CONFIDENCE(0.05,2.5,50) → 0.692951912
95% interval, sd 2.5, n 50.
Larger sample
=CONFIDENCE(0.05,15,100) → 2.939945977
Larger sample.
99%
=CONFIDENCE(0.01,15,100) → 3.863743937
99% interval.
Worth knowing
- Identical to CONFIDENCE.NORM.
- CONFIDENCE.T for small samples.
- Alpha is 1 minus the confidence level.
Where it goes wrong
- #NUM! for invalid alpha, sd, or size.
- Flagged by the Compatibility Checker.
Related
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