A sports scientist conducted an experiment to investigate whether consuming a high-caffeine energy drink before a gaming session decreases reaction times compared to a placebo drink. An independent measures design was used, testing 14 esports athletes. Seven participants consumed the high-caffeine energy drink, while the remaining seven consumed a taste-matched placebo. Their reaction times (measured in milliseconds) were recorded during a standardized virtual reflex test. The raw data is presented in the table below.
| Reaction time (ms) with High-Caffeine or Placebo | |||
|---|---|---|---|
| High-Caffeine | Placebo | ||
| Participant | Time (ms) | Participant | Time (ms) |
| 1 | 185 | 1 | 195 |
| 2 | 192 | 2 | 240 |
| 3 | 188 | 3 | 180 |
| 4 | 190 | 4 | 265 |
| 5 | 183 | 5 | 205 |
| 6 | 189 | 6 | 170 |
| 7 | 191 | 7 | 225 |
Explain what information the standard deviation would provide if it was calculated for the reaction time data in this study.
513 exam-style questions on OCR A Level Psychology Data recording, analysis and presentation. Each one has a worked solution and a mark scheme showing where the marks go.