Standard Deviation Formula:
| From: | To: |
Dispersion measures how spread out a set of data is from its central value (mean). Standard deviation is the most common measure of dispersion, representing the average distance of each data point from the mean.
The calculator uses the standard deviation formula:
Where:
Explanation: The formula calculates the square root of the average squared differences from the mean, providing a measure of data variability.
Details: Understanding dispersion is crucial for statistical analysis, risk assessment, quality control, and interpreting data variability in research and business applications.
Tips: Enter numerical values separated by commas. The calculator will compute the mean, sum of squared differences, and standard deviation automatically.
Q1: What's the difference between population and sample standard deviation?
A: Population standard deviation divides by n, while sample standard deviation divides by n-1 (Bessel's correction) to account for sampling bias.
Q2: When is standard deviation preferred over variance?
A: Standard deviation is in the same units as the original data, making it more interpretable than variance (which is squared).
Q3: What does a high standard deviation indicate?
A: High standard deviation means data points are spread out widely from the mean, indicating high variability or uncertainty.
Q4: Can standard deviation be negative?
A: No, standard deviation is always non-negative since it's derived from squared differences and square roots.
Q5: How is dispersion used in real-world applications?
A: Used in finance for risk measurement, quality control for process variability, research for data reliability, and weather forecasting for prediction uncertainty.