Equation 17 · Retrieval Is an Evidence System, Not a Memory
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Read the formula alongside the article passage below. Each part has a deeper page with its role in the equation, the supporting passage and nearby citations.
This mathematical expression combines the displayed quantities; its precise role follows from the surrounding article text. Read the equation part by part below; each part has a contextual explanation and a link to its mathematical background.
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Symbol Z_k
is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Symbol x
x is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
subscript
The lower label selects a particular version, component, or indexed member of the quantity. For example, x₀ and xₜ can be values at different positions.
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What the article says around this equation
Because retrieval and generation are separable, an end-to-end score is nearly uninformative about which one broke. Decompose it. Let be the retrieved set and S(x) the set of spans that would suffice to answer x :
Sources cited in the article section
- [6] BEIR: A Heterogenous Benchmark for Zero-shot Evaluation of Information Retrieval Models ↗
- [17] Ragas: Automated Evaluation of Retrieval Augmented Generation ↗
- [18] Benchmarking Large Language Models in Retrieval-Augmented Generation ↗
These citations give research context. Read each source to check which claims it supports.
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