Title: logit transformation
Long Title: IUPAC Gold Book - logit transformation
DOI: 10.1351/goldbook.14812
Status: current

Definition
In competitive binding assays, the logit-log dose relationship, in which the response is defined by \[R = {\rm{logit}}\,(y) = \ln [y/(1 - y)]\] where \(y = b/b_{0}\), \(b\) is fraction of tracer bound and \(b_{0}\) is the value of \(b\) with no unlabelled ligand in the system.

Note
Logit-transformed assay data frequently yield straight-line dose-response data, amenable to statistical analysis. More generally in toxicology, the transformation is applied to dose-response data where \(b_{0}\) denotes the maximum response in the absence of a toxic substance.

Source
- PAC, 2009, 81, 829. 'Glossary of terms used in ecotoxicology (IUPAC Recommendations 2009)' on page 907 (https://doi.org/10.1351/PAC-REC-08-07-09)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/14812/html
- json: https://goldbook.iupac.org/terms/view/14812/json
- xml: https://goldbook.iupac.org/terms/view/14812/xml

Citation: Citation: 'logit transformation' 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.14812
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Accessed: 2026-06-28T23:59:59+00:00