Standard deviation
Definition
The square root of the variance. Expressed in the same units as the original measurement, making it interpretable as a typical distance from the mean. The most commonly reported measure of spread in forensic data.
Related terms
- Mean
- The arithmetic average of a dataset, calculated as the sum of all values divided by the number of values. Sensitive to extreme...
- Median
- The middle value of a dataset sorted in ascending or descending order. For an even number of values, it is the average...
- Mode
- The value that appears most frequently in a dataset. Most informative for discrete or categorical data; for continuous measurement data it is...
- Refractive index (RI)
- A physical property of glass measuring how much light bends as it passes through. RI is the primary discriminating characteristic used in...
- Variance
- The average of the squared deviations from the mean. Because it squares the original unit of measurement, variance is not directly interpretable...
Explained in
- Descriptive Statistics for Forensic DataThe square root of the variance. Expressed in the same units as the original measurement, making it interpretable as a typical distance from the mean. The most...