An engine manufacturing facility wants to apply machine learning to detect faulty bolts.

The syllabus defines bias as:

"Bias is the systematic difference in treatment of certain objects, people or groups in comparison to others."

It also discusses:

"Sample bias can occur if the data used for training the model does not represent the operational environment, or if some relevant faulty conditions are excluded deliberately."

(Reference: ISTQB CT-AI Syllabus v1.0, Section 7.6 and 8.3)