When should I use sample vs population SD?

Use sample SD when your data is a subset of a larger group. Use population SD when you have all the data.

What does a high standard deviation mean?

It means data points are spread far from the average, indicating high variability.

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Standard Deviation Calculator

Calculate mean, variance, and standard deviation for any dataset.

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Standard deviation, mean, and variance of your dataset.

Standard Deviation

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What is Standard Deviation?

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Standard deviation measures the spread of data around the mean. A low SD means data is clustered close to the mean; a high SD means it is spread out.

Standard Deviation Formula

Sample and population SD formulas.

Sample SD

s = √(Σ(x - x̄)² / (n-1))

Use for a sample from a larger population.

Population SD

σ = √(Σ(x - μ)² / n)

Use when you have data for the entire population.

Frequently Asked Questions

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Sample SD

Population SD

Frequently Asked Questions

When should I use sample vs population SD?

What does a high standard deviation mean?

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