8.1. Approaching a Machine Learning Problem8.1.1. Humans in the Loop8.2. From Prototype to Production8.3. Testing Production Systems8.4. Building Your Own Estimator8.5. Where to Go from Here8.5.1. Theory8.5.2. Other Machine Learning Frameworks and Packages8.5.3. Ranking, Recommender Systems, and Other Kinds of Learning8.5.4. Probabilistic Modeling, Inference, and Probabilistic Programming8.5.5. Neural Networks8.5.6. Scaling to Larger Datasets8.5.7. Honing Your Skills8.6. Conclusion