Machine Learning Ensemble Methods

Sample Images from MNIST Dataset

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This project investigates the power of ensemble machine learning models for the MNIST dataset. The individual components are made up of

  • Random Forests
  • Extra Trees
  • Support Vector Machines

Two varieties of ensembling are constructed. They are

Ensemble 1 - Soft Voting Classifier

Sample Images from MNIST Dataset

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This combines the 3 classifier algorithms and performs a voting mechanism to determine the class that the image belongs to.

Ensemble 2 - Stacking Classifier

Sample Images from MNIST Dataset

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Stacking Classifier uses a two tier architecture. In the first stage, the output of three classifier are stacked and fed into a random forest classifier. This mimics a feature extraction stage followed by classifier, which is quite common in deep neural networks.

Results

Individual Models
Model Test Set Accuracy
(in percentage)
Random Forests 96.87
Extra Forests 97.07
Support Vector Machines 96.46
Ensemble Models
Model Test Set Accuracy
(in percentage)
Soft Voting Classifier 97.42
Stacking Classifier 97.08