How to prevent data leakage during AG News 4-Class Topic Classification preprocessing?

Always perform train_test_split BEFORE fitting any normalization scaler (like StandardScaler) or categorical encoders. Fit scalers strictly on the training partition and call .transform() on validation data.

HOME DATASETSAG News 4-Class Topic Classification

NLP / Multi-class Topics120,000 RECORDS 7-STEP PYTORCH BLUEPRINT

AG News 4-Class Topic Classification

Standard benchmark for multi-class news article classification with GloVe embeddings, BiLSTM, and 1D-CNN.

LAUNCH 7-STEP WORKSPACE EXPLORE ALL DATASETS

TARGET / PREDICTIONTopic: World (0), Sports (1), Business (2), Sci/Tech (3)

FEATURE SHAPENews article headlines & description text

TASK OBJECTIVEmulticlass classification

RECOMMENDED MODELnn.EmbeddingBag -> nn.Linear(embed_dim, 128) -> ReLU -> Dropout -> nn.Linear(128, 4)

RAW RECORD SAMPLE INSPECTION

Columns: ID, Text_Snippet, Label, Word_Count, Sentiment_Polarity

ID	Text_Snippet	Label	Word_Count	Sentiment_Polarity
ag_01	Wall St. Bears Claw Back Gains: Retail sales slump triggers defensive rotation into consumer staples.	Business (2)	16	-0.24
ag_02	NASA Mars Rover Uncovers Ancient Hydrated Silica Deposits in Jezero Crater.	Sci/Tech (3)	13	+0.45
ag_03	Champions League: Real Madrid Secures Dramatic Stoppage-Time Victory in Semifinal Thriller.	Sports (1)	14	+0.80
ag_04	Diplomatic Summit Concludes with Historic Multilateral Accord on Renewable Grid Infrastructure.	World (0)	13	+0.62

7-STEP PYTORCH CURRICULUM ROADMAP

ESTIMATED TIME: ~30 MINS

STEP 1Ingestion & AuditLoad raw tensors and check for null values without data leakage.

STEP 2 & 3Transforms & DataLoadersFit scaling on Train only and package into mini-batch DataLoaders.

STEP 4 & 5Architecture & LossConstruct PyTorch nn.Module with AdamW and loss criterion.

STEP 6 & 7Training & CheckpointingRun autograd training loop, evaluate under no_grad, and export .pth weights.

FREQUENTLY ASKED QUESTIONS (FAQS)

How do I load AG News 4-Class Topic Classification into a PyTorch DataLoader?

Subclass torch.utils.data.Dataset, implement __len__ and __getitem__ returning (features, target) tensor pairs, and wrap the dataset with torch.utils.data.DataLoader(dataset, batch_size=32, shuffle=True).

What neural network architecture is best for AG News 4-Class Topic Classification?

We recommend using nn.EmbeddingBag -> nn.Linear(embed_dim, 128) -> ReLU -> Dropout -> nn.Linear(128, 4). For tabular data, a Multi-Layer Perceptron (MLP) with BatchNorm and Dropout works best; for vision, Convolutional Neural Networks (CNNs); and for sequential text, LSTM or Recurrent Language Models.

How do I prevent data leakage during preprocessing?

Never fit scalers (like StandardScaler or Normalization transforms) on the entire dataset prior to splitting. Always execute train_test_split first, call scaler.fit_transform(X_train) on the training partition only, and use scaler.transform(X_val) on validation data.