Equation 1 · AI Inference Economics in Practice: An Advanced Technical Guide
What does this equation mean?
Read the formula alongside the article passage below. Each part has a deeper page with its role in the equation, the supporting passage and nearby citations.
This mathematical expression combines the displayed quantities; its precise role follows from the surrounding article text. Read the equation part by part below; each part has a contextual explanation and a link to its mathematical background.
Read it piece by piece
Symbol w
w is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
How to interpret it
Read this expression with the definitions, units, and assumptions supplied by the article.
What the article says around this equation
That convergence on roughly one tenth of base input for a cache read — independently verified today across all three platforms [ 2 , 6 , 10 ] — supports a design rule. Let w be the write-price multiplier for the chosen retention window and r 0.1 the read-price multiplier. For a prefix served identically R times within that window — the first serving is the write, the remaining R-1 are reads — caching beats never caching once
Sources cited in the article section
- [5] Prompt Caching ↗
- [2] Prompt Caching ↗
- [9] Context Caching ↗
- [6] Pricing ↗
- [10] Gemini Developer API Pricing ↗
These citations give research context. Read each source to check which claims it supports.
Return to AI Inference Economics in Practice: An Advanced Technical Guide