| Typicality: | 0.438 |
| Saliency: | 0.441 |
| to his further research | 12 | purpose |
| to understanding their origins | 9 | purpose |
| to a man | 2 | transitive-object |
| observation → be → key | 25 |
| observation → be → the key | 14 |
| negative | neutral | positive |
| 0.042 | 0.598 | 0.361 |
| Raw frequency | 39 |
| Normalized frequency | 0.441 |
| Modifier score | 0.500 |
| Perplexity | 29.323 |