Questions worth following

Investigations

This will become a collection of concrete situations and questions: a place to begin with what you need to understand.

A few provisional starting points:

• Are these IDs actually unique?
• Why does one extract behave differently?
• What changed between these files?
• What can I trust to identify a person?
• Where should I start with unfamiliar data?

These are questions for future investigations. The worked material is still to come.