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TruncNormal

Continuous normal prior truncated to a finite interval.

Parameters

Argument Symbol Meaning Default
low \(\ell\) Lower truncation bound -6.0
high \(h\) Upper truncation bound 6.0
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

This is a true truncated normal on the closed interval [low, high]. The density is the underlying normal renormalized over that interval; the implementation does not use clipped or censored point masses at the bounds.

PDF

\[ f(x;\mu,\sigma,\ell,h)= \frac{\phi\!\left(\frac{x-\mu}{\sigma}\right)} {\sigma\left[\Phi\!\left(\frac{h-\mu}{\sigma}\right)-\Phi\!\left(\frac{\ell-\mu}{\sigma}\right)\right]} \]

Region

\[ x \in [\ell,h] \]