Table 1 List of dependency features
From: Identifying genotype-phenotype relationships in biomedical text
| Features | Description |
|---|---|
| Relationship term | Root of the portion of the dependency tree connecting phenotype and genotype |
| Stemmed relationship term | Stemmed by Mallet |
| Relative position of relationship term | Whether it is before the first entity, after the second entity or between them |
| The relationship term combined with the dependency relationship | To consider the grammatical role of the relationship term in the dependency path. |
| The relationship term and its relative position | |
| Key term | Described in Ibn Faiz’s four step method [48] |
| Key term and its relative position | |
| Collapsed version of the dependency path | All occurrences of nsubj/nsubjpass are replaced with subj, rcmod/partmod with mod, prep x with x and everything else with O, a placeholder to indicate that a dependency has been ignored. |
| Second version of the collapsed dependency path | Only the prep_* of dependency relationships are kept. |
| Negative dependency relationship | A binary feature that shows whether there is any node in the path between the entities which dominates a neg dependency relationship. This feature is used to catch the negative relationships. |
| prep_between | A binary feature that checks for the existence of two consecutive prep_between links in a dependency path. |