theta_{s} ~ DirSym(alpha, T), s \in [1,S] pi_{d} ~ DirSym(gamma, S), d \in [1,D] phi_{s,t} ~ DirSym(beta, V), s \in [1,S], t \in [1,T] l_{d,n} ~ Mult(pi_{d}), d \in [1,D] , n \in [1,N_{d}] z_{d,n} ~ Mult(theta_{l_{d,n}}), d \in [1,D] , n \in [1,N_{d}] w_{d,n} ~ Mult(phi_{l_{d,n}, z_{d,n}}), d \in [1,D] , n \in [1,N_{d}]