A team of aerospace engineers is testing two types of wind-speed sensors, Sensor X and Sensor Y, on 8 experimental drone flights. The readings (in knots) are recorded below:
| Flight | A | B | C | D | E | F | G | H |
|---|---|---|---|---|---|---|---|---|
| Sensor X | 12 | 15 | 8 | 22 | 19 | 5 | 25 | 10 |
| Sensor Y | 14 | 18 | 6 | 20 | 24 | 7 | 23 | 9 |
Calculate Spearman's rank correlation coefficient for these readings.
Test, at the 5% level of significance, whether there is a positive correlation between the sensors' readings. State your hypotheses clearly.
Sensor Y's reading for Flight F was later corrected to 6 knots. Explain how you would calculate Spearman's rank correlation coefficient in this case, without performing any new calculations.
340 exam-style questions on Edexcel A Level Maths Regression, Correlation and Hypothesis Testing, covering 1.1 Exponential Models, 1.2 Measuring Correlation, and 1.3 Hypothesis Testing for Zero Correlation. Each one has a worked solution and a mark scheme showing where the marks go.