Equation 42 · Part 4 · The Economics of Codex: Tokens, Sandboxes, Review Time, and Software Throughput

Symbol d_t

h_{t+1}=h_t+\ell_t-d_t,

d_t

What this part means

depreciation of skills no longer exercised.

Its job in the formula

$d_t$ is one of the signed contributions combined to compute the quantity on the left.

Full expressionSymbol d_tArticle meaning

Where the article explains it

where $\ell_t$ is learning from agent-assisted work and $d_t$ is depreciation of skills no longer exercised.

The passage around this formula

Let developer capability evolve as $h_{t+1}=h_t+\ell_t-d_t$ . where $\ell_t$ is learning from agent-assisted work and $d_t$ is depreciation of skills no longer exercised. Both depend on workflow. Requiring developers to predict behavior, inspect evidence, and explain accepted changes can raise $\ell_t$ . Delegating opaque work and reviewing only summaries can raise $d_t$ .

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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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Sources cited in the article section

[2] Models ↗

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