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Data Annotation Tools and Workflows

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Choosing annotation tools and designing workflows that produce consistent, high-quality labels.

Editorial team 1 min read

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Labelled data powers supervised learning and evaluation. Tools and workflows determine its quality.

Tool Types

  • Open-source annotation tools for text, images, audio and video.
  • Commercial platforms with workforce management.
  • Managed labelling services.
  • Custom interfaces for specialised tasks.

Choosing Tools

  • Support for your data types and label formats.
  • Collaboration, review and quality control features.
  • Security and data residency.
  • Integration with your data pipelines.

Workflow Design

  1. Guidelines: clear definitions with examples and edge cases.
  2. Pilot: label a small batch, measure agreement, refine guidelines.
  3. Production labelling with regular spot checks.
  4. Review: second-pass review of disagreements and difficult items.
  5. Feedback: update guidelines as new cases appear.

Model-Assisted Labelling

Pre-label with a model and have people correct it. Faster, but watch for people accepting wrong suggestions.

Labeller Welfare

Content moderation and sensitive material can harm labellers. Provide support, rotation and fair pay.

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