Dr. Aris investigated the effect of high-intensity cognitive training on spatial reasoning under stress. He recorded the number of navigation errors made by five trained fighter pilots during a simulated flight test consisting of 12 critical decision junctions.
The error scores are shown in Table 1.
Calculate the standard deviation for the navigation error scores using the data in Table 1. Show your working and give your answer to two decimal places.
Table 1: Navigation error scores for five trained pilots
| Pilot | Navigation errors (out of 12) |
|---|---|
| P | 2 |
| Q | 4 |
| R | 5 |
| S | 8 |
| T | 11 |
638 exam-style questions on Edexcel A Level Psychology Methods. Each one has a worked solution and a mark scheme showing where the marks go.