| to the central nervous system | 5 | transitive-object |
| in humans | 3 | other |
| caffeine → be → stimulant | 33 |
| caffeine → act as → stimulant | 12 |
| caffeine → be → natural stimulant | 9 |
| caffeine → be → mild stimulant | 3 |
| negative | neutral | positive |
| 0.259 | 0.469 | 0.273 |
| Raw frequency | 57 |
| Normalized frequency | 0.904 |
| Modifier score | 0.500 |
| Perplexity | 9.167 |