EWT — known annotation errors

Gist. EWT is the base of mova, so the converter does not fix its errors: otherwise the round trip EWT → mova → EWT would stop being identity. Errors are caught by seed rules (en/seeds, error level) and tagger suspicions. Fixes are a separate layer of edits, not a dialect.

Conditions and exceptions. Numbers — en expert-check en/seeds on all parts of EWT 2.18: error-level violations out of matches.

Examples and numbers.

• compound to the right of the head (en.nominal.compound-head-final) — 23 of 8690: email-enronsent21_02-0030 EY4096.1 PERFORMANCE.

• Infinitive VB under Do, while Do is not aux (en.verbal.vb-aux-infinitive) — 7 of 3888: email-enronsent08_02-0045 Do … take.

• aux on a non-finite head (en.verbal.aux-head-nonfinite) — 6: could … missed.

• what as det:predet (en.nominal.predet-xpos, det-is-det) — 5: reviews-287360-0002 What ….

• Imperative with inconsistent features (en.verbal.imperative-form, imperative-aux-do-only) — 2 + 2: reviews-326439-0002 TRY.

• Free relatives annotated as interrogatives — a known problem from the README (Known Issues), not caught by a rule.

• General counters (English UD 2.18 treebanks — comparative seed) give small residues on EWT:

  • tb.en.imp-mood — 38 of 3066;
  • tb.en.propn-number — 475 of 16,562 PROPN without Number;
  • tb.en.obl-fragment — 12 of 196;
  • tb.en.num-feats — 15 of 5051;
  • tb.en.pron-lemma — 9 of 5039.

  Some of them are edge cases rather than errors.

• Typo=Yes — 1431, of which 1429 have CorrectForm in MISC. These are not annotation errors but marked text errors; about 200 more were added in 2.18.

In UD. Of the 213 error-level rules in en/seeds, only 16 have violations on EWT train, 1–17 cases per rule. Almost all of them are errors of EWT itself (An expert system for English grammar: seeds and rules, "Self-check on gold data"). Under "examples are not truth" these are tagger and parser suspicions, not a reason to change mova.

Sources. README UD_English-EWT, Known Issues («Many free relatives are incorrectly analyzed as interrogative»), v2.18 («Mark about 200 tokens as typos»); An expert system for English grammar: seeds and rules; en — Mova's English graph compressor, "Examples are not truth".

This page in Markdown → https://md.mova.elamur.ai/free/en/docs/treebanks/en/ewt/seeds/errors/