Title: aliased effects
Long Title: IUPAC Gold Book - aliased effects
DOI: 10.1351/goldbook.10066
Status: current

Definition
In a fractional-factorial design, effects for which the information obtained are identical.

Note
In a two-level design, the product of the coded levels for the aliased effects are equal.

Example
If there are four factors in a design: \(\rm{A,\ B,\ C,\ D}\) then the main effect of \(\rm{A}\) can be aliased with the three-way effect \(\rm{B} \times \rm{C} \times \rm{D}\). So for the run that has \(\rm{B} = -1\), \(\rm{C} = -1\), \(\rm{D} = +1\), then \(\rm{A}\) must \(= +1\).

Related Terms
- effects: https://goldbook.iupac.org//terms/view/10068
- fractional-factorial design: https://goldbook.iupac.org//terms/view/10073

Source
- PAC, 2016, 88, 407. 'Vocabulary of concepts and terms in chemometrics (IUPAC Recommendations 2016)' on page 413 (https://doi.org/10.1515/pac-2015-0605)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/10066/html
- json: https://goldbook.iupac.org/terms/view/10066/json
- xml: https://goldbook.iupac.org/terms/view/10066/xml

Citation: Citation: 'aliased effects' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.10066
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Accessed: 2026-04-21T09:40:36+00:00