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Equation 37 · Part 9 · The Real Economics of Shipping a Model to a Device

subscript

Qdevice∗=(Cdev+U)/(ccloud−cd)Q^{*}_{\mathrm{device}} = (C_{\mathrm{dev}} + U) / (c_{\mathrm{cloud}} - c_{d})
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.

The passage around this formula

The marginal-cost argument for on-device inference is not wrong; it is one term in a four-term equation, and the other three — variant-matrix engineering, distillation-versus-teacher economics, and update-distribution bandwidth — are each individually documented at real, checkable magnitudes in this article. Distillation itself is nearly always worth doing: disclosed training runs in the hundreds of dollars clear their own break-even point against even modest cloud query volumes almost immediately. Placing the result on a device is a separate, harder calculation, one that rises with every additional tier a release has to validate and every device already in the field that has to receive the…

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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 →

The article lists its research sources here.