Vocabulary

Understand the term. Connect the concept.

A practical dictionary of 512 AI, machine learning, mathematics, and programming terms from HerbDev’s AI Vocabulary app. Start with a definition, explore an example, then follow the concepts behind it.

Linked concepts open in a new tab. Audio reads the definition and example.

Accuracy

Model Evaluation · Level 2 of 5

Accuracy

The fraction of evaluated predictions that are correct.

It can hide poor performance on rare classes.

Example

Ninety correct labels out of one hundred give 90 percent accuracy.

Listen to the definition and example

Audio transcript

Accuracy. The fraction of evaluated predictions that are correct. It can hide poor performance on rare classes. For example: Ninety correct labels out of one hundred give 90 percent accuracy.

Explore this concept

A useful analogy

The share of all answers marked correct on a test.

Why it matters

This helps you ask what a reported score counts and which errors it can hide.

Technical detail

Accuracy = correct / total. In single-label binary classification it equals (TP + TN) / (TP + TN + FP + FN).

Common misconception

A high accuracy can come from always choosing a very common class.

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Classification

Related concepts

Quick recall question

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Put the terminology into context: How AI works · Machine-native representations · All learning paths

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