Measures of Variability
Summary of Standard Deviation
-
-
- S.D. is the most used and most important measure of dispersion. Related to Variance.
- Arithmetic operations can be performed with it
- Most stable measure of dispersion.
- 68% of the scores fall ±1 S.D.
- 95.4% of the scores fall ±2 S.D.
- 99.74% of the scores fall ±3 S.D.