Step-by-step guide to calculating standard deviation for population data.

Review of population and sample standard deviation, including the formula and interpretation.

Sal explains a different variance formula and why it works! For a population, the variance is calculated as σ² = ( Σ (x-μ)² ) / N. Another equivalent formula is σ² = ( (Σ x²) / N ) - μ². If we …

This video explains normal distribution problems using the empirical rule.

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Learn to calculate the variance and standard deviation of a discrete random variable.

Khan Academy

Опа. Нещо се обърка. Моля, опитай отново. Опа, изглежда, че нещо се обърка. Трябва да обнови ...

If I take a sample, I don't always get the same results. However, sampling distributions—ways to show every possible result if you're taking a sample—help us to identify the different results …