allowable

Definition

Within a budget you agreed to in advance, most often in the phrase allowable error. In approximate algorithms and compact data structures the allowable error is an input, not an outcome: you declare how wrong an answer may be and how often, and the required space falls out of that choice. Seeing the word signals a design that deliberately trades exactness for resources rather than one that failed to be exact.

Explainers using this term

• Probabilistic Data Structures — Counting Without CountingSpace/Time Trade-offs in Hash Coding with Allowable Errors (Bloom