Equation 4 · Part 2 · Ten Failure Modes That Show Up Across Every Frontier Model, Not Just One

subscript

\Delta_{\text{contamination}}

subscript

What this part means

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.

Its job in the formula

A subscript distinguishes a version, component, step, or member of a quantity. It does not automatically mean multiplication.

Full expressionsubscriptArticle meaning

The passage around this formula

$\Delta_{\text{contamination}}$ is inflation from the model having seen the benchmark, or something close to it, during training. $\Delta_{\text{configuration}}$ is variance from everything about how the question was asked, formatted, and scored — prompt wording, decoding settings, which variant answered. Both terms are provider-specific and time-specific; neither is disclosed by the headline number. Three of the ten failure modes below are different ways that $\Delta_{\text{contamination}}$ and $\Delta_{\text{configuration}}$ get large without the label on the chart changing.

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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.

Open the illustrated subscripts: which member of a family? guide →

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