Equation 17 · Part 1 · Retrieval Is an Evidence System, Not a Memory
Symbol Z_k
What this part means
is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
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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 Z_k→Article meaning
The passage around this formula
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 :
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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 provide research context; check each source for the exact claim it supports.