How to Calculate ‘r’ by Hand
Introduction & Importance
Calculating ‘r’, the correlation coefficient, is crucial in statistics to understand the relationship between two variables. This guide walks you through calculating ‘r’ by hand and provides real-world examples.
How to Use This Calculator
- Enter the sample size (n), sample mean (x̄), and standard deviation (s).
- Click ‘Calculate’.
- View the result and chart below.
Formula & Methodology
The formula for ‘r’ is:
r = Σ[(Xi – X̄)(Yi – Ÿ)] / √[Σ(Xi – X̄)² * Σ(Yi – Ÿ)²]
Real-World Examples
Data & Statistics
| Dataset | r |
|---|---|
| Dataset 1 | 0.85 |
| Dataset 2 | 0.52 |
Expert Tips
- Understand the range of ‘r’ values.
- Interpret ‘r’ with caution; it only shows strength and direction, not causation.
Interactive FAQ
What does ‘r’ measure?
‘r’ measures the strength and direction of the linear relationship between two variables.
For more information, see Office for National Statistics and U.S. Census Bureau.