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LogNormal

Canonical lognormal prior family on positive support.

Parameters

Argument Symbol Meaning Default
mean \(\mu\) Mean of the underlying normal distribution 0.0
std \(\sigma\) Standard deviation of the underlying normal distribution 1.0
random_state - RNG seed / generator None
Implementation Parameterization

The API takes the underlying normal parameters directly: X = exp(N(mean, std**2)). No additional shift or scale wrapper parameters are exposed.

PDF

\[ f(x;\mu,\sigma) = \frac{1}{x\sigma\sqrt{2\pi}} \exp\left(-\frac{(\log x-\mu)^2}{2\sigma^2}\right) \]

Region

\[ x \in (0,\infty) \]