Equation 18 · Part 13 · How a Model Actually Gets Small Enough to Run on a Phone
subscript
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 expression→subscript→Article meaning
The passage around this formula
SparseGPT poses pruning as a per-layer reconstruction problem. For a layer with weight matrix W and a small calibration set of activations X , it looks for a sparse replacement W' that keeps that layer’s output as close as possible to the original: . Rather than solving this by retraining, Frantar and Alistarh adapt a closed-form update derived from the layer’s second-order (Hessian) information, in the spirit of the older Optimal Brain Surgeon method, so that whenever a weight is removed the remaining weights in that row are analytically nudged to compensate for its absence. The result, reported for the GPT-family models tested, is that “large-scale generative pretrained…
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 →
Sources cited in the surrounding passage
These citations provide research context; check each source for the exact claim it supports.