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C

Z-score

How many standard deviations a value is from the mean of its distribution.

z = (x − μ) / σ. A z-score of 0 means a value sits exactly at the mean; ±1 means one standard deviation away; ±2 means two.

Z-scores let you compare values from differently-scaled distributions on the same axis. They're also the input to a normal-distribution lookup table for computing probabilities.

Calculators that use this

Z-score CalculatorStandardized z-score.P-value CalculatorP-value from a z-statistic.Confidence Interval CalculatorCI for a mean.
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