The Craig plot, named after Paul N. Craig, is a plot of two substituent parameters (e.g. Hansch-Fujita π constant and sigma constant) used in rational drug design.
Two most used forms of a Craig plot are plotting the sigma constants of the Hammett equation versus hydrophobicity plotting the steric terms of the Taft equation against hydrophobicity
See also Quantitative structure-activity relationship pKa
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Further reading