reduction

Definition

Any operation that makes something smaller — dimensions, memory, compute cost, variance. The word rarely stands alone: the modifier in front tells you what shrinks, as in dimensionality reduction or cost reduction, and papers are expected to quantify the factor saved. A separate sense lives in distributed training, where a reduction such as all-reduce folds values from many devices into one.

Explainers using this term

• Unsupervised Learning from Scratch — Clustering and Dimensionality ReductionUMAP: Uniform Manifold Approximation and Projection for Dimension Reduction