Decoder. plain-English AI glossary

Adversarial Example

● Core

Also called Adversarial Example

An input tweaked in a way humans barely notice but that makes the model badly wrong.

Think of it like

An optical illusion tuned for a machine — a tiny sticker on a stop sign that makes a car read it as "speed limit 45."

Example

A few carefully chosen pixels added to a panda photo, invisible to you, make an image classifier label it a gibbon with high confidence.

How it actually works

Models draw decision boundaries in high-dimensional space, and those boundaries have exploitable seams. An adversarial example nudges an input just across a boundary — often imperceptibly — to force a confident wrong answer. It started in image classifiers but applies to text and audio too. It reveals something uncomfortable: high accuracy on normal inputs doesn’t mean the model is robust to inputs an adversary designed on purpose.

For product teams

A reminder that "works great in the demo" and "safe against attackers" are different guarantees.

For engineers

Small, often imperceptible perturbations that cross a decision boundary; robustness requires adversarial training or defenses, not just clean accuracy.

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