Coefficient of Variation (CV)
The coefficient of variation (CV) is a super useful statistical tool that helps us compare the variability between different sets of data, even when they have different units or vastly different means. Let's break this down into bite-sized pieces!
What is the Coefficient of Variation?
The coefficient of variation is a standardized measure of dispersion that expresses variability relative to the mean. It's calculated as:
CV = [Standard Deviation / Mean] x 100%
The CV is always expressed as a percentage, making it easier to interpret and compare different datasets.
Why Do We Use CV?
The CV becomes particularly valuable in sports and exercise science when we need to:
- Compare variability between different types of measurements
- Assess the reliability of testing procedures
- Evaluate the consistency of athletic performance
Let's say we want to compare the consistency of two athletes:
- Athlete A: Mean jump height = 50cm, SD = 5cm
- Athlete B: Mean jump height = 80cm, SD = 7cm
CV for Athlete A = (5/50) × 100% = 10% CV for Athlete B = (7/80) × 100% = 8.75%
Despite having a larger standard deviation, Athlete B actually shows more consistency in their performance!
