Free Standard Error Calculator
Calculate the standard error of the mean, which measures how much the sample mean varies from sample to sample.
Standard Error
3.000000
Variance of the Mean9.0000
Relative SE (as % of SD)20.0000
Standard Error vs Standard Deviation
How to Calculate the Standard Error
Formula
SE = sigma / sqrt(n)
The standard error of the mean measures the precision of the sample mean as an estimator of the population mean. It is the standard deviation of the sampling distribution of the mean. As sample size increases, SE decreases, making estimates more precise.
Example Calculation
Population SD = 15, sample size = 25. What is the standard error?
- 01SE = sigma / sqrt(n)
- 02SE = 15 / sqrt(25)
- 03SE = 15 / 5 = 3
- 04Variance of mean = 15^2 / 25 = 225 / 25 = 9
Frequently Asked Questions
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