HalfCauchy
Heavy-tailed positive prior family.
Parameters
| Argument | Symbol | Meaning | Default |
|---|---|---|---|
gamma |
\(\gamma\) | Half-Cauchy scale parameter | 1.0 |
random_state |
- | RNG seed / generator | None |
Implementation Parameterization
The implementation uses the canonical half-Cauchy family on [0, \infty).
No shift parameter is exposed.
\[
f(x;\gamma) =
\frac{2}{\pi\gamma\left(1 + \left(\frac{x}{\gamma}\right)^2\right)}
\]
Region
\[
x \in [0,\infty)
\]