Hold-out validation
Hold-out validation is an evaluation procedure that partitions data once into separate subsets for model fitting and assessment.
Deep Learning with R, Third Edition
Hold-out validation is an evaluation procedure that reserves a subset of available data for assessment without using it to fit the model.
- How it is used
- Evaluates generalization during model development by reserving validation data for performance measurement and decision-making.
- How deep it goes
- Explains the split, training loop, test separation, leakage risk, and small-data limitation, then points to K-fold alternatives.
- Examples
- Uses indexed data partitioning, model fitting, validation scoring, final retraining, and test evaluation.
- What you can do after
- Apply it by splitting data, tuning against validation metrics, retraining after decisions, and reserving the test set for final evaluation.
Read how Deep Learning with R, Third Edition explains hold-out validation →
Deep Learning with Python, Third Edition
An evaluation protocol that splits data once into separate subsets for training, validation, and/or testing.
- How it is used
- Uses a single data split to estimate validation performance while preserving a separate test set for final generalization measurement.
- How deep it goes
- Explains the split, training, evaluation, retraining, and small-data caveat, then defers repeated partitioning to K-fold methods.
- Examples
- Demonstrates shuffled array slicing, model fitting, validation evaluation, and final retraining with combined training and validation data.
- What you can do after
- Apply hold-out validation by splitting data, fitting a model, checking validation performance, and reserving test data for final evaluation.
Read how Deep Learning with Python, Third Edition explains hold-out validation →
Related concepts
- cross-validationalternative to · Cross-validation is a resampling technique that evaluates a model by repeatedly fitting it on some portions of available data and assessing it on held-out portions.
- evaluation datasetuses · An evaluation dataset is a collection of examples or test cases, often with expected or judged outcomes, designated to assess a model or system against defined criteria.
- training datasetimplements · A collection of examples or observations supplied to a learning procedure to fit or adapt a model or learn its patterns or parameters.
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