23 Simplex Distributions

The simplex probabilities have support on the unit \(K\)-simplex for a specified \(K\). A \(K\)-dimensional vector \(\theta\) is a unit \(K\)-simplex if \(\theta_k \geq 0\) for \(k \in \{1,\ldots,K\}\) and \(\sum_{k = 1}^K \theta_k = 1\).