Equation 10 · Part 1 · Measuring AI Agent Reliability: What the Evidence Actually Supports
Symbol k
What this part means
the number of samples.
Its job in the formula
k 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 k→Article meaning
Where the article explains it
The obvious approach — generate exactly k samples per problem and check whether any of them pass — has an undesirable property: it is a valid estimate but a high-variance one, since it throws away information every time you happen to generate more or fewer than k samples.
The passage around this formula
Pass@k answers a specific question: given a budget of k independent attempts, what is the chance that at least one succeeds? That is the right question for a search-and-verify workflow, where a cheap checker can identify the one attempt that worked among several candidates. It is the wrong question for almost everything else an agent does, because…
Learn the underlying idea
A variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.
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Sources cited in the surrounding passage
These citations provide research context; check each source for the exact claim it supports.