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Software Engineering vocabulary · Machine Learning and Data Processing

Class imbalance

Meaning in software engineering, with examples

nounCommon term

In software engineering, class imbalance means: A situation in which some classes in a dataset have far more examples than others, for example 990 normal transactions for every 10 fraudulent ones.

In Turkish: sınıf dengesizliği

How it is used

Very common in fraud, medical and defect detection. It makes accuracy misleading, so teams look at precision, recall and F1 instead. Typical fixes are resampling, class weights in the loss function and collecting more examples of the rare class.

Example sentences

  1. Because of the class imbalance, the model learned to predict 'no defect' for almost everything.

  2. We handled the class imbalance by oversampling the rare class.

Common collocations

  • severe class imbalance
  • handle class imbalance
  • imbalanced dataset
  • class weights
  • accuracyThe share of a model's predictions that are correct, out of all its predictions. A model with 90% accuracy is right on nine of every ten examples.
  • F1 scoreA single number that combines precision and recall by taking their harmonic mean. It is high only when both precision and recall are high.
  • recallOf all the cases that really were positive, the share that the model managed to find. High recall means few missed cases.
  • datasetA collection of examples, such as images, texts or table rows, gathered and organized for training, testing or analyzing a model.

This word in other fields

The same English word can have a different meaning in another field:

More terms: Machine Learning and Data Processing

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