Statistics and probability
Variance
The average squared deviation from the mean under the selected population or sample convention.
Common notationσ²=Σ(xᵢ−μ)²/N
In one sentence
What does Variance mean?
The average squared deviation from the mean under the selected population or sample convention.
How it is written
σ²=Σ(xᵢ−μ)²/N
A compact example
For 1, 2 and 3, population variance is 2/3.
Where this fits
When should you learn Variance?
The first encounter is not the final level. Many ideas begin visually, become computational in high school and become formal in college.
- 1Pre-high schoolPrepare foundations
- 2High schoolUsually introduced
- 3CollegeGreater depth
- 4AdvancedGreater depth
- Statistics
- Probability
- Fractions
- Percentages
- Sets
- Distributions
- Inference
- Quantum probability
Quantum predictions are expressed through probabilities and expected values.
Open the Zero-to-QM pathClear answers
Questions about Variance
What does Variance mean in mathematics?
The average squared deviation from the mean under the selected population or sample convention.
How is Variance written?
A common notation is σ²=Σ(xᵢ−μ)²/N.
What is an example of Variance?
For 1, 2 and 3, population variance is 2/3.