What is the square root of variance?
Understand the Problem
The question is asking for the calculation of the square root of variance, which is a statistical concept. The square root of variance is known as the standard deviation, and the question seeks to identify this relationship.
Answer
The standard deviation is the square root of the variance: $\text{Standard Deviation} = \sqrt{\text{Variance}}$.
Answer for screen readers
The standard deviation is defined as the square root of the variance.
Steps to Solve
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Identify the Definition The square root of the variance is known as the standard deviation. This relationship can be expressed as: $$ \text{Standard Deviation} = \sqrt{\text{Variance}} $$
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Understanding Variance Let's denote the variance as $V$. The calculation of variance depends on the individual data points and the mean. For a set of data points $x_1, x_2, \ldots, x_n$, the variance is calculated as: $$ V = \frac{1}{n} \sum_{i=1}^{n} (x_i - \mu)^2 $$ where $\mu$ is the mean of the data points.
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Calculating the Square Root Once you have the variance $V$, you find the standard deviation by taking the square root: $$ \text{Standard Deviation} = \sqrt{V} $$
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Example Calculation If, for example, the variance is $V = 16$, then the standard deviation can be calculated as follows: $$ \text{Standard Deviation} = \sqrt{16} = 4 $$
The standard deviation is defined as the square root of the variance.
More Information
The standard deviation provides insight into how spread out the numbers in a data set are. A low standard deviation indicates that the numbers tend to be close to the mean, while a high standard deviation indicates that the numbers are spread out over a wider range.
Tips
- Confusing variance with standard deviation is a common mistake; remember that variance is in squared units while standard deviation is in the same units as the data.
- Forgetting to take the square root of the variance when calculating standard deviation.