Section 11: Lab: Decision Trees, Random Forests and Boosting
- Decision trees, node splits and limiting depth to reduce overfitting
- Random forests and the idea of bagging ensembles
- HistGradientBoosting for large tabular datasets and categorical features
- Explain models with feature importance and permutation_importance
Section 12: Unsupervised Learning: K-Means and PCA
- Segment customers with K-Means and choose the number of clusters with the elbow method and silhouette score
- Interpret the clusters so the business can act on them
- Reduce dimensions with PCA and read the explained variance
- Plot high-dimensional data in two dimensions to explore patterns
Section 13: Lab: Face Recognition with Eigenfaces
- Understand the Olivetti Faces dataset and turn images into vectors
- Find a suitable number of principal components and display the eigenfaces
- Build a PCA and SVM pipeline and tune it with cross-validation
- Evaluate the system and analyse the faces it gets wrong
- Care points for face data, consent and PDPA
Section 14: Lab: Putting Models to Use
- Save and load models with skops, and the risks of pickle files
- Record library versions and training data so results can be reproduced
- Build a demo page with Gradio so others can try the model
- Use AI assistants to help write ML code, then check and re-evaluate every result
Section 15: Workshop: Capstone Project
- Choose a problem and dataset and define the success metrics
- Prepare the data, build a pipeline and compare at least three models
- Tune the best model, check it against the test set and summarise its limits
- Present the work with a demo page and plan the next step into deep learning