In an aerospace engineering trial, 7 experimental prototype wings were tested in a wind tunnel to determine the relationship between atmospheric pressure, ppp (kPa), and the resulting lift coefficient, LLL. The data collected is presented in the table below:
| Prototype Unit | A | B | C | D | E | F | G |
|---|---|---|---|---|---|---|---|
| Pressure, ppp | 45 | 52 | 60 | 68 | 75 | 83 | 91 |
| Lift, LLL | 0.42 | 0.48 | 0.46 | 0.55 | 0.51 | 0.62 | 0.58 |
Calculate the value of Spearman's rank correlation coefficient between ppp and LLL.
Stating your hypotheses clearly, test at the 5% level of significance whether there is evidence of a positive correlation between atmospheric pressure and lift coefficient.
The product moment correlation coefficient (PMCC) for these data is calculated as r=0.8881r = 0.8881r=0.8881.
Use the given PMCC value to test, at the 5% level of significance, whether there is evidence of a positive correlation between pressure and lift.
Based on your conclusions from parts (b) and (c), describe the nature of the relationship between atmospheric pressure and lift coefficient.
178 exam-style questions on WJEC A Level Maths 4.3.1 Statistical hypothesis testing (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.