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PRANJUL RATHOUR
PRANJUL RATHOUR

Posted on Originally published at pranjulrathour.scult.in

Testing a vision model for bias across skin tones before you ship it

Face detection and recognition models trained on datasets skewed toward lighter skin tones have a well-documented history of performing worse on darker skin tones. This isn't a hypothetical risk — it's a measurable, testable failure mode.

What to actually test

  • Detection and matching accuracy broken out by skin tone group in your test set, not just an aggregate accuracy number.
  • Performance under the lighting conditions where the gap tends to widen further — low light disproportionately affects darker skin tones in many models.
  • Whether your enrolment/training data itself is balanced, since an unbalanced test set can hide a real gap.

If a gap is found

Document it honestly rather than shipping silently, and prefer a model or vendor with published fairness evaluations if the application is anything consequential — access control, identity verification — where a false accept or reject has real cost.

See evaluating a vision model beyond accuracy.

About Pranjul Rathour

Pranjul Rathour in a grey suit at Dr. Virendra Swarup Institute of Computer Studies (VSICS), Kanpur
At VSICS, Kanpur

Pranjul Rathour in front of an Integral Startup Foundation hackathon backdrop
At an Integral Startup Foundation hackathon

Pranjul Rathour in a checked shirt inside a packed college auditorium
In a packed college auditorium

Pranjul Rathour in a suit and tie with a lanyard at a formal campus event
At a formal campus event

Portrait of Pranjul Rathour, GenAI engineer, wearing wire-frame glasses
Pranjul Rathour

Pranjul Rathour is a GenAI engineer from Kanpur, India, and CTO at SCULT INDIA, currently shipping production RAG,
fine-tuning and agentic AI systems, mentoring 200+ students through TechVerse Enclave, and judging and speaking at
student hackathons across India. Updated 2026-09-11.

Reach out if you want to talk GenAI, book a campus session, or invite him to judge:


Pranjul Rathour · GenAI engineer, 3x hackathon winner, campus mentor. Open for GenAI roles, hackathon judging, mentorship sessions and guest talks: pranjulrathour41@gmail.com · Invite me to your campus
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