Measures of Dispersion (Spread of Data):
- Range: Simplest measure; Difference between maximum and minimum values. Sensitive to outliers.
- Interquartile Range (IQR): Q3 - Q1 (difference between 75th and 25th percentiles). Less sensitive to outliers.
- Variance: Average of the squared differences from the Mean.
- Standard Deviation: Square root of the variance. Most common measure of dispersion.
Measures of Central Tendency: Mean, Median, Mode.
Lorenz Curve: Used to show income/wealth inequality.