Term: surprisal, \(s\)
https://doi.org/10.1351/goldbook.S06195

Definition:
A function relating the prior distribution P 0 of product states to an observed or calculated product distribution P. It is defined by: \[s=- \ln (\frac{P}{P_{0}})\]

Related Terms:
1) prior distribution (http://doi.org/10.1351/goldbook.P04852).

Source: PAC, 1996, 68, 149. 'A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)' on page 188 (https://doi.org/10.1351/pac199668010149)

Citation: 'surprisal, \(s\)' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.S06195

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