Deep Learning Approach¶
This section outlines the deep learning methodology used for the Store Sales - Time Series Forecasting project.
Methodology¶
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Data Preprocessing & Cleaning:
Raw sales, oil, holiday, and store data are merged, missing values are handled, and categorical variables are encoded using one-hot encoding. -
Feature Engineering:
Lag-based features, rolling statistics, and calendar-based features (such as day of week, holidays, and paydays) are generated to capture temporal patterns and external influences on sales. -
Exploratory Data Analysis (EDA):
Data distributions, trends, and correlations are visualized to inform feature selection and model design. -
Model Development:
The primary model is a feedforward neural network implemented in Keras/TensorFlow. The architecture consists of multiple dense layers with ReLU activations and dropout regularization to prevent overfitting. -
Training Strategy:
The Adam optimizer is used with a learning rate of 0.001. Early stopping is employed to halt training when validation loss stops improving, ensuring optimal generalization. -
Evaluation:
Model performance is monitored using Mean Squared Error (MSE) and Mean Absolute Error (MAE) on a validation set. The final model is saved and used for inference on the test set.
Model Architecture¶
- Input Layer: Accepts engineered features for each store-date-family combination.
- Hidden Layers: Two dense layers (96 and 64 units) with ReLU activation and dropout.
- Output Layer: Single neuron with linear activation for sales prediction.
Training and Optimization¶
- Optimizer: Adam (learning rate = 0.001)
- Loss Function: Mean Squared Error (MSE)
- Batch Size: 64
- Epochs: Up to 20, with early stopping (patience = 4)
- Regularization: Dropout (rate = 0.1) to reduce overfitting
Reproducibility & Automation¶
- All steps, from data preparation to model training and inference, are automated via modular scripts.
- Model checkpoints and logs are saved for transparency and reproducibility.
This deep learning approach is designed to capture both short-term and long-term sales patterns, leveraging rich feature engineering and modern neural network techniques to deliver accurate forecasts for the Kaggle Store Sales competition.