Standard Deviation Calculator

Standard Deviation Calculator computes the dispersion of a dataset from its mean, enabling statistical variance analysis for academic, financial, or research data.

Standard Deviation Calculator

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Descriptive Statistics

Count (N):8
Sum (Σx):144
Mean (μ):18

Population (Entire Group)

Standard Deviation (σ):4.8989795
Variance (σ²):24

Sample (Subset of Group)

Sample Standard Deviation (s):5.2372294
Sample Variance (s²):27.428571

What is Standard Deviation?

Standard deviation is a statistical measure that tells you how dispersed or spread out the numbers in a dataset are from the mean (average).

  • Low Standard Deviation: The data points tend to be very close to the mean.
  • High Standard Deviation: The data points are spread out over a large range of values.

Population vs. Sample

It is crucial to know whether your dataset represents an entire Population or just a Sample (a subset) of the population.

  • Population Standard Deviation (σ): Used when you have data for every single member of the group you are studying. Formula divides by N.
  • Sample Standard Deviation (s): Used when you only have a sample of the population. Formula divides by N - 1 (Bessel's correction) to provide an unbiased estimator.