วันศุกร์ที่ 10 กรกฎาคม พ.ศ. 2569

Leave-One-Out Cross-Validation

 Leave-One-Out Cross-Validation (LOOCV) is a specific type of K-fold cross-validation where the number of folds (K) equals the total number of data points (N) in your dataset.

Here is how it works in a nutshell:

  • The Process: If you have N data points, you train your model N times. In each iteration, you "leave out" exactly one data point to use as the test set and train the model on the remaining N-1 data points.

  • The Evaluation: You record the model's error on that single held-out point. After rotating through all data points, you average the N individual errors to get the final validation score.