Equation 15 · Part 1 · Naive, Graph, and Agentic: A Systems Comparison of RAG Architectures
Symbol C_index
What this part means
the writing.
Its job in the formula
ndex is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Full expression→Symbol C_index→Article meaning
Where the article explains it
Writing for the one-time cost of building the graph and its community summaries, and for the cost of answering a single query against the finished structure, the amortised cost of a query workload of size Q against one graph is
The passage around this formula
This is the one family among the five whose defining engineering trade-off is temporal rather than architectural: cost is shifted from query time to index time. Writing for the one-time cost of building the graph and its community summaries, and for the cost of answering a single query against the finished structure, the amortised cost of a query workload of size Q against one graph is
Learn the underlying idea
A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.
Open the illustrated subscripts: which member of a family? guide →
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Sources cited in the article section
- [4] From Local to Global: A Graph RAG Approach to Query-Focused Summarization ↗
- [5] GraphRAG: Get Started ↗
- [6] LazyGraphRAG: Setting a New Standard for Quality and Cost ↗
These citations provide research context; check each source for the exact claim it supports.