Standard deviation is a statistical measure that quantifies the amount of variation or dispersion within a dataset. It provides information about how spread out the values in a dataset are from the mean (average) value. In other words, the standard deviation indicates the degree of variability or the average distance between individual data points and the mean.
The standard deviation is calculated by taking the square root of the variance. Variance measures the average squared difference of each data point from the mean. By taking the square root of the variance, the standard deviation is obtained in the same unit of measurement as the original data, making it more interpretable.
A low standard deviation indicates that the values in the dataset are closely clustered around the mean, indicating less variability or dispersion. On the other hand, a high standard deviation suggests that the data points are spread out over a wider range from the mean, indicating greater variability or dispersion.
Standard deviation is commonly used in various fields such as statistics, finance, and scientific research to assess the spread or variability of data. It provides a useful measure to compare the degree of dispersion between different datasets or to evaluate the consistency or precision of measurements. Additionally, the concept of standard deviation is employed in many statistical techniques, such as hypothesis testing and constructing confidence intervals, to analyze and interpret data.