Count independent layout families
Start with source organization, document generator, template version, and document type. A thousand files can share one underlying template. Request approximate layout-family counts and examples from each major family so you can estimate how much genuine structural variation the collection contains.
Separate visual and semantic variation
Color changes and logos may alter appearance without changing where information lives. Conversely, a consistent-looking form can use different field meanings. Track page structure, field arrangement, table shape, and semantic differences separately. This helps prevent a visually diverse sample from concealing a narrow extraction task.
Include page-level challenges
Specify the proportions of scans, native PDFs, rotated pages, dense tables, faint text, and attachments. Define whether handwriting is in scope. Include the conditions you expect at deployment, but retain a baseline of readable documents so a failure analysis can separate layout reasoning from basic legibility.
Hold out meaningful families
Keep related templates and near-duplicates together when constructing evaluation splits. Ask reviewers to document the grouping decision rather than relying only on random file assignment. Discuss target layout coverage with Fiund alongside language, business process, source provenance, and the fields needed for the planned model task. For a concrete review exercise, compare three files from one vendor with three files from three unrelated vendors. Ask which structural decisions change and which remain identical. This helps your team agree on what counts as a distinct layout family before using that number to describe the collection’s independent evaluation coverage.
Review checklist
- Count templates as well as files
- Track structure separately from branding
- Define scan and readability coverage
- Reserve independent layout families for evaluation