Equation 4 · Part 1 · How Benchmark Contamination Actually Works in Agentic Evaluation

Symbol Delta_checker

\Delta_{\text{checker}}

\Delta_{\text{checker}}

What this part means

inflation from a verifier that can be satisfied by something other than a correct solution — a weak test suite, a policy that exploits how success is graded rather than what it is graded on.

Its job in the formula

Delt $a_c$ hecker is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

Full expressionSymbol Delta_checkerArticle meaning

Where the article explains it

$\Delta_{\text{checker}}$ is inflation from a verifier that can be satisfied by something other than a correct solution — a weak test suite, a policy that exploits how success is graded rather than what it is graded on.

The passage around this formula

…solve genuinely novel instances of this task class. $\Delta_{\text{leak}}$ is inflation from the environment itself disclosing the solution — through its history, its documentation, or a live network path to the answer. $\Delta_{\text{checker}}$ is inflation from a verifier that can be satisfied by something other than a correct solution — a weak test suite, a policy that exploits how success is graded rather than what it is graded on. $\Delta_{\text{fingerprint}}$ is a shift, in either direction, from the policy…

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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.

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