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ZDD - [Z] Asymmetric Normal
This is the Zero Distortion Density (ZDD) used in the GenHVL[Z] models. This generalized normal's a1 center parameter is the mean of the underlying Normal. The default ZDD is a similar model with a parameterization where a1 is the mean of the asymmetric peak. The a3 parameter in the ZDD nomenclature adjusts the third moment or skew.
This is also the ZDD used in the GenNLC[Z] models. For the GenNLC[Z] models, a0, a1 will be identical. The a2 width or second moment term will reflect a kinetic time constant, and a3 will reflect an NLC asymmetry normalized to 0.5 for the Giddings ZDD. Please see the GenHVL and GenNLC equivalence topic for further details.
a0 = Area
a1 = Center (as mean of underlying Gaussian)
a2 = Width (as SD of underlying Gaussian)
a3 = Asymmetry ( fronted -1 > a3 > 1 tailed)
Built-In Peak Model
GenNorm (Statistical family)
User-Defined Peaks and View Functions
GenNorm(x,area,median,width,shape) Asym Generalized
GenNorm_C(amplitude,center,width,z-asym) Gen. Normal cumulative
GenNorm_CR(amplitude,center,width,z-asym) Gen. Normal reverse cumulative