AI engineering glossary · Evaluation metrics
What is accuracy?
Accuracy: The fraction of all predictions that are correct: (TP + TN) / (TP + TN + FP + FN). It is simple and easy to explain, but it misleads when one class is far more common than the other, because a model that always predicts the majority class can still score very high.
Accuracy: an example
If a model gets 985 of 1,000 transactions right, its accuracy is 0.985 or 98.5%, even though it may have missed a quarter of the frauds.
Related terms
More Evaluation metrics terms
- Accuracy paradox
- Adjusted Rand index
- AUC-ROC
- Average precision
- Balanced accuracy
- BERTScore
- Bits per byte
- BLEU
Where you learn it
Accuracy is part of the AI Engineering Program, which teaches it with notes, a hands-on lab and an exam. The first lesson is free.