What's changed: Initial: 2 sections for Domain 5 (testing, validation, and troubleshooting)
5.1Evaluation Systems for GenAI
Learn to systematically evaluate FM output quality: Bedrock Model Evaluations, RAG evaluation, LLM-as-a-Judge, Bedrock Agent evaluations, A/B and canary testing, relevance/factual/consistency/fluency metrics, and regression testing.
GenAI cannot be measured by traditional ML accuracy alone. Evaluate multi-dimensionally—relevance, factual accuracy, consistency, fluency—combining automated and human evaluation to ensure quality.
5.1.1Evaluation methods
- Bedrock Model Evaluations: systematically evaluate models/configurations to identify optimal settings (automated metrics + human).
- LLM-as-a-Judge: use another FM as an evaluator to auto-score output quality at scale.
- RAG/Agent evaluation: assess retrieval+generation with RAG evaluation, and task completion/tool use/reasoning quality with Bedrock Agent evaluations.
- A/B/canary/regression: A/B and canary for production comparison, pre/post-deploy regression tests and quality gates, and user feedback for continuous improvement.
Common: systematic model/config evaluation = Bedrock Model Evaluations, auto-score at scale = LLM-as-a-Judge, retrieval+generation quality = RAG evaluation, agent task completion = Agent evaluations, safe production comparison = A/B/canary. Axes: relevance/factual/consistency/fluency.
Evaluation combines metrics, automation, and production validation. Define output quality with multi-dimensional metrics (relevance, factual accuracy, consistency, fluency), and systematize model/config comparison with Bedrock Model Evaluations (automated metrics + human). Scale with LLM-as-a-Judge (an evaluator FM scores), complemented by human annotation (e.g., SageMaker Ground Truth). Assess RAG with RAG evaluation (retrieval relevance + generation faithfulness) and agents with Bedrock Agent evaluations (task completion, tool-use effectiveness, multi-step reasoning quality). Promote to production safely via A/B / canary, stop regressions with pre/post-deploy regression tests and automated quality gates, and validate AI-specific output (hallucination rate, semantic drift) with synthetic user flows (e.g., CloudWatch Synthetics). Communicate results to stakeholders via visualization reports/model comparisons, and close the loop with user feedback for continuous improvement.
| Target | Use | Measures |
|---|---|---|
| Model/config comparison | Bedrock Model Evaluations | Automated metrics + human |
| Quality scoring at scale | LLM-as-a-Judge | Relevance/factual/consistency |
| RAG quality | RAG evaluation | Retrieval relevance + faithfulness |
| Agent quality | Agent evaluations | Task completion/tool use |
Trap: “accuracy alone measures GenAI quality” is wrong—evaluate generation across relevance, factual accuracy, consistency, and fluency. Also “LLM-as-a-Judge fully replaces human evaluation” is wrong—it scales automation but complement critical judgments with human evaluation/Ground Truth.
5.1.2Section summary
- Systematic = Model Evaluations / at scale = LLM-as-a-Judge / RAG = RAG evaluation / agents = Agent evaluations
- Production = A/B·canary + regression + quality gates / axes = relevance/factual/consistency/fluency
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Quick check
(just a quick review)Q1. You want to systematically compare which of several FMs/configurations best fits your use case, using both automated metrics and human evaluation. Best option?
Q2. You want to auto-score quality (relevance, factual accuracy, etc.) of tens of thousands of generated answers at scale and consistently, without relying on humans alone. Best method?
Q3. When promoting a new prompt version to production, you want to compare and validate quality on real traffic while limiting impact on existing users. Best option?
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