In JMP 14 the SHASHInv function is supposed to be defined by the following mathematical equation:
SinH( (ArcSinH( x ) - gamma) / delta ) * sigma + theta;
However, there is a bug in JMP 14 where the SHASHInv function does not match the results of the mathematical formula.
In JMP 14 the function SHASHInv should not be used, but instead the actual formula should be used. The formula can be found by clicking on Help ► Scripting Index and then searching for "SHASHInv."
This issue is fixed in JMP® 15.
[Previously JMP Note 67553]