Summarization Score Evaluator
The Summarization Score evaluates how well a system-generated response summarizes information from the context documents. It assesses various aspects of summary quality, including conciseness, completeness, accuracy, and relevance to the query.

Summarization Score component interface and configuration
Evaluation Notice: The quality of summarization depends on the ability to distill key information while maintaining accuracy. This metric is particularly useful when the RAG system is expected to condense lengthy source information into a more digestible format.
Component Inputs
- Generated Summary: The summarized response produced by the RAG system
Example: "Quantum computing leverages qubits that can exist in multiple states simultaneously through quantum superposition..."
- Contexts: The source documents or additional context used for evaluation
Example: ["Quantum computing uses quantum bits or qubits that can exist in multiple states simultaneously due to quantum superposition..."]
Component Outputs
- Evaluation Result: Qualitative assessment of the summary's strengths and weaknesses
Example: "The summary effectively condenses the key information from the source while maintaining accuracy and completeness."
Score Interpretation
Excellent Summarization (0.7-1.0)
Summary effectively condenses information while maintaining completeness, accuracy, and relevance to the query
Example Score: 0.92
This indicates an excellent summary that captures the essential information concisely
Adequate Summarization (0.3-0.7)
Summary captures some key information but may be imbalanced, too verbose, or missing some important elements
Example Score: 0.50
This indicates a summary that addresses the topic but has significant room for improvement
Poor Summarization (0.0-0.3)
Summary misses key points, includes irrelevant information, or misrepresents the source content
Example Score: 0.15
This indicates a summary that fails to effectively capture and condense the source information
Implementation Example
from ragas.metrics import SummarizationScore
# Create the metric
summarization = SummarizationScore()
# Use in evaluation
from datasets import Dataset
from ragas import evaluate
eval_dataset = Dataset.from_dict({
"question": ["Summarize the key features of
quantum computing."],
"contexts": [["Quantum computing uses quantum
bits or qubits that can exist in multiple states +
simultaneously due to quantum superposition. This +
parallelism allows quantum computers to solve +
certain problems exponentially faster than classical +
computers. Another key feature is quantum +
entanglement, which creates strong correlations +
between qubits regardless of distance. Quantum +
computers are particularly promising for cryptography,
materials science, and optimization problems."]],
"answer": ["Quantum computing leverages qubits
that can exist in multiple states simultaneously
through quantum superposition, enabling exponential +
computational speedups. It also utilizes quantum +
entanglement to create correlations between qubits. +
These features make quantum computers especially +
useful for cryptography, materials science, and +
optimization problems."]
})
result = evaluate(
eval_dataset,
metrics=[summarization]
)
print(result)
Use Cases
- Information Distillation: Evaluate RAG systems designed to extract and condense key information from longer documents
- Research Assistants: Assess systems that summarize multiple research papers or documents to provide concise overviews
- Content Briefing: Evaluate tools that create executive summaries or briefings from comprehensive source materials
- Documentation Synthesis: Measure the quality of summaries generated from technical or complex documents
- News Summaries: Assess systems that condense news articles while preserving key facts and context
Best Practices
- Combine with ROUGE and BLEU metrics for comprehensive evaluation of summary quality
- Consider domain-specific requirements when interpreting summarization scores
- Assess both information coverage and conciseness when evaluating summaries
- Compare the summarization quality across different prompt strategies
- Balance completeness with brevity according to the specific use case requirements