{"term":{"id":"14954","title":"probit log transform","longtitle":"IUPAC Gold Book - probit log transform","doi":"10.1351\/goldbook.14954","code":"14954","status":"current","definitions":[{"id":1,"text":"Probability unit obtained from the standardized normal distribution plotted against the logarithm of the concentration or dose of a substance when a quantal or graded response has been measured. A linear plot provides evidence that the distribution is log-normal. Estimates of the \\(\\pu{L(E)C_{50}}\\) and \\(\\pu{L(E)D_{50}}\\), as well as the standard deviation for the distribution, can then be made.","links":[{"term":"graded response","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/14722"},{"term":"quantal","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/14965"}],"sources":["PAC, 2009, 81, 829. 'Glossary of terms used in ecotoxicology (IUPAC Recommendations 2009)' on page 932 (https:\/\/doi.org\/10.1351\/PAC-REC-08-07-09)"]}],"altoutputs":{"html":"https:\/\/goldbook.iupac.org\/terms\/view\/14954\/html","xml":"https:\/\/goldbook.iupac.org\/terms\/view\/14954\/xml","plain":"https:\/\/goldbook.iupac.org\/terms\/view\/14954\/plain"},"citation":"Citation: 'probit log transform' 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.14954","license":"The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/) for individual terms.","collection":"If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org .","disclaimer":"The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.","accessed":"2026-04-18T21:13:07+00:00"}}