AWS Machine Learning Specialty Study Guide (Retired MLS-C01 Exam)

This guide covers the AWS Certified Machine Learning - Specialty exam (MLS-C01), which AWS has retired. The domain breakdown and study plan below describe the former exam and are kept for reference and for anyone renewing their study on the underlying ML topics.

Former Exam Overview (Retired)

• Certification: AWS Machine Learning
• Exam Code: MLS-C01
• Vendor: AWS
• Cost: $300 USD
• Duration: 180 minutes
• Questions: 65 questions
• Passing Score: 750 out of 1000
• Format: Multiple choice and multiple response
• Prerequisites: None required (2+ years hands-on ML/deep learning on AWS recommended)

Domain Breakdown

Understanding the exam domains and their weights is critical for efficient study planning. Focus more time on heavily-weighted domains while ensuring you cover all areas.

Domain 1: Data Engineering (20%)

• 1.1 Create data repositories for machine learning
• 1.2 Identify and implement data ingestion solutions
• 1.3 Identify and implement data transformation solutions

Key concepts: S3 Data Lakes and Lake Formation, Kinesis Data Streams vs Firehose, AWS Glue ETL Jobs and Crawlers, Glue Data Catalog, EMR with Spark for Large-Scale Processing, Athena for Ad-Hoc Querying, Data Pipeline Orchestration, Batch vs Real-Time Ingestion

Domain 2: Exploratory Data Analysis (24%)

• 2.1 Sanitize and prepare data for modeling
• 2.2 Perform feature engineering
• 2.3 Analyze and visualize data for machine learning
• 2.4 Select appropriate statistical methods for data analysis

Key concepts: Handling Missing Data (Imputation Strategies), Outlier Detection and Treatment, One-Hot Encoding vs Label Encoding, Normalization vs Standardization, Principal Component Analysis (PCA), t-SNE for Visualization, Correlation Analysis, Class Imbalance (SMOTE, Oversampling)

Domain 3: Modeling (36%)

• 3.1 Frame business problems as machine learning problems
• 3.2 Select the appropriate model for a given problem
• 3.3 Train machine learning models
• 3.4 Perform hyperparameter optimization
• 3.5 Evaluate machine learning models

Key concepts: SageMaker Built-In Algorithms (XGBoost, Linear Learner, KNN), Image Classification and Object Detection, Sequence-to-Sequence (Seq2Seq) Models, BlazingText and Word2Vec, Random Cut Forest (Anomaly Detection), Hyperparameter Tuning Jobs, Confusion Matrix, Precision, Recall, F1, AUC-ROC Curves

Domain 4: Machine Learning Implementation and Operations (20%)

• 4.1 Build ML solutions for performance, availability, scalability, resiliency, and fault tolerance
• 4.2 Recommend and implement appropriate ML services and features for a given problem
• 4.3 Apply security practices to ML solutions

Key concepts: SageMaker Real-Time Endpoints, Batch Transform Jobs, Multi-Model Endpoints, SageMaker Model Monitor (Data Drift), SageMaker Pipelines (MLOps), Model Registry and Versioning, A/B Testing with Production Variants, Auto-Scaling Inference Endpoints

Recommended Study Timeline

Plan for approximately 10-16 weeks of dedicated study. Here is a suggested weekly breakdown:

• Week 1: Domain 1: Data Repositories (S3 data lakes, Redshift, RDS, DynamoDB for ML pipelines)
• Week 2: Domain 1: Data Ingestion (Kinesis Data Streams/Firehose, Glue ETL, Data Pipeline, batch vs streaming)
• Week 3: Domain 1: Data Transformation (Glue DataBrew, EMR Spark, Athena, feature engineering techniques)
• Week 4: Domain 2: Data Sanitization (Missing values, outliers, normalization, encoding categorical variables)
• Week 5: Domain 2: Feature Engineering. Feature selection, dimensionality reduction (PCA), data visualization
• Week 6: Domain 2: Data Analysis (Statistical analysis, correlation, distribution analysis, SageMaker Data Wrangler)
• Week 7: Domain 3: ML Frameworks (SageMaker built-in algorithms, XGBoost, Linear Learner, image classification)
• Week 8: Domain 3: Model Training (Hyperparameter tuning, training jobs, distributed training, Spot instances)
• Week 9: Domain 3: Evaluation (Confusion matrix, precision/recall, F1 score, AUC-ROC, overfitting/underfitting)
• Week 10: Domain 4: SageMaker Endpoints (Real-time inference, batch transform, multi-model endpoints, auto-scaling)
• Week 11: Domain 4: MLOps (SageMaker Pipelines, Model Registry, Model Monitor, A/B testing, CI/CD for ML)
• Week 12: Domain 4: Security & Cost (VPC configs, KMS encryption, IAM roles, Spot training, instance selection)
• Week 13: Full Review: Practice exams, SageMaker hands-on labs, Algorithm review, Exam logistics
• Week 14: Final Review: Weak areas deep-dive, Full-length practice tests, Time management strategies

Top Study Tips

1. Start with the official exam objectives. Download them from the AWS website and use them as your study checklist. Every exam question maps to a specific objective.

1. Use active recall over passive reading. Instead of re-reading notes, test yourself with practice questions after each study session. This dramatically improves retention.

1. Focus on heavily-weighted domains first. Domains with higher percentages appear more on the exam. Master these before moving to lower-weighted areas.

1. Build hands-on experience. Set up a lab environment and practice the skills you are studying. Hands-on experience is especially valuable for performance-based questions.

1. Take practice exams under real conditions. Time yourself, eliminate distractions, and simulate the exam environment. Review every wrong answer and understand why it was wrong.

Practice Resources

Test your knowledge with our free tools:

Take our free AWS Machine Learning practice quiz

• CVSS Calculator: Practice scoring vulnerabilities
• Password Strength Checker: Test password security

Career Impact

The AWS Machine Learning certification demonstrates validated expertise to employers. Certified professionals typically see:

• Higher starting salaries compared to non-certified peers
• More interview callbacks as the certification signals commitment and competence
• Faster career progression with a recognized credential on your resume
• Access to roles that specifically require or prefer AWS Machine Learning certification

What to Study Next

After earning your AWS Machine Learning certification, consider these natural next steps:

• Deepen your specialization with an advanced certification in the same vendor track
• Broaden your skills with a certification from a complementary domain
• Visit our Career Paths page for detailed certification roadmaps

Get Organized with a Study Planner

A structured study plan makes the difference between passing and failing. Our fillable PDF study planners include domain trackers, weekly schedules, and progress tracking designed specifically for AWS Machine Learning exam prep.

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This guide is independently created for educational purposes. AWS trademarks belong to their respective owners. FixTheVuln is not affiliated with or endorsed by AWS.