Table 2.

Potential issues during data collection and checks to resolve them.

Potential Issue	Automatic validation	Manual validation
The geometry of the language polygon was traced incorrectly.	Perform a geometry check and fix any invalid geometries.	Visually inspect the digitised geometry against the language area in the source map.
The language name was copied incorrectly.	Verify that a language with the name copied from the map exists on Glottolog.	Cross-check the copied name with the source map.
The numeric language label was copied incorrectly.	Verify that the copied numeric label exists in the map legend.	Check the copied label against the source map legend.