AWS Certified Machine Learning - Specialty (MLS-C01) Domain 3
Modeling
Official Exam Guide: Domain 3: Modeling
Skill Builder: AWS Certified Machine Learning - Specialty Exam Prep
Domain Overview
Domain 3 (36% - largest domain) focuses on framing business problems as ML problems, selecting appropriate models, training models, hyperparameter optimization, and evaluating models.
Task 3.1: Frame business problems as ML problems
Key Concepts:
- Determine when to use/not use ML
- Supervised vs unsupervised learning
- Problem types: classification, regression, forecasting, clustering, recommendation, foundation models
Essential Documentation:
Task 3.2: Select appropriate model(s)
Key Algorithms:
- XGBoost, logistic regression, k-means, linear regression, decision trees, random forests
- RNN, CNN, ensemble methods, transfer learning, LLMs
- Express intuition behind models
Essential Documentation:
- XGBoost Algorithm
- Linear Learner Algorithm
- K-Means Algorithm
- Random Cut Forest
- DeepAR Forecasting Algorithm
- Image Classification Algorithm
- Object Detection Algorithm
Task 3.3: Train ML models
Key Concepts:
- Split data (training/validation, cross-validation)
- Optimization techniques (gradient descent, loss functions, convergence)
- Compute resources (GPU/CPU, distributed/non-distributed, Spark/non-Spark)
- Model updating (batch, real-time/online)
Essential Documentation:
- Train a Model with Amazon SageMaker
- Distributed Training
- SageMaker Data Parallelism
- SageMaker Model Parallelism
Task 3.4: Perform hyperparameter optimization
Key Concepts:
- Regularization (dropout, L1/L2)
- Cross-validation
- Model initialization
- Neural network architecture (layers, nodes, learning rate, activation functions)
- Tree-based models (number of trees, depth)
- Linear models (learning rate)
Essential Documentation:
Task 3.5: Evaluate ML models
Key Concepts:
- Avoid overfitting/underfitting (bias-variance tradeoff)
- Metrics: AUC-ROC, accuracy, precision, recall, RMSE, F1 score
- Confusion matrices
- Offline and online evaluation (A/B testing)
- Model comparison (training time, quality, engineering costs)
- Cross-validation
Essential Documentation:
AWS Service FAQs
Study Tips
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Master algorithm selection - Classification (XGBoost, random forest), Regression (linear learner), Clustering (k-means), Forecasting (DeepAR), Computer Vision (CNN), NLP (RNN, transformers).
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Learn evaluation metrics - Classification: accuracy, precision, recall, F1, AUC-ROC. Regression: RMSE, MAE, R². Confusion matrix interpretation.
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Understand hyperparameter tuning - SageMaker automatic model tuning, Bayesian optimization, random search, grid search strategies.
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Practice bias-variance tradeoff - Overfitting (high variance): regularization, more data. Underfitting (high bias): more features, complex model.
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Study training optimization - Distributed training strategies, gradient descent variants (SGD, Adam), learning rate schedules, early stopping.
Note: This is Domain 3 of 4, representing 36% (largest domain) of exam content.