π What is Overfitting?
Overfitting is when your language model (LM) is too good at remembering the training data but bad at generalizing to new, unseen data π¬.
Think of it like this:
π Training Data = Your school textbook
π§ Overfitted Model = A student who memorized every page but struggles with test questions that are worded differently.
π¨ Signs Your LM is Overfitted
1. π Low Training Loss, π High Validation/Test Loss
- Your model is doing GREAT on the training set π but performs poorly on validation/test data π.
β
Training loss: Low
β Validation/Test loss: High
2. πͺ Huge Gap Between Accuracy or Perplexity
If you’re tracking accuracy or perplexity (a measure for language models):
- Accuracy on training = 90%+ π―
- Accuracy on validation = 50%-60% π
Thatβs a big red flag π©
3. π Your Loss Curve Looks Like This:
- Training loss keeps going down π
- Validation loss goes down first, then goes back up π
That’s a classic overfitting curve π§ π₯
π οΈ How to Fix It?
β
Use more data
β
Regularization techniques like dropout π³οΈ
β
Early stopping βΉοΈ
β
Smaller model if data is limited
β
Data Augmentation (e.g., paraphrasing for text)