Ejemplo n.º 1
0
    def build_prior_KL(self):
        # whitening of priors can be implemented here
        """
        This gives KL divergence between inducing points priors and approximated posteriors

        KL(q(u_g)||p(u_g)) + KL(q(u_f)||p(u_f))

        q(u_f) = N(u_f|u_fm,u_fs)
        p(u_f) = N(u_f|0,Kfmm)

        q(u_g) = N(u_g|u_gm,u_gs)
        p(u_g) = N(u_g|0,Kgmm)

        """

        if self.whiten:
            if self.q_diag:
                KL = kullback_leiblers.gauss_kl_white_diag(self.u_fm, self.u_fs_sqrt) + \
                     kullback_leiblers.gauss_kl_white_diag(self.u_gm, self.u_gs_sqrt)
            else:
                KL = kullback_leiblers.gauss_kl_white(self.u_fm, self.u_fs_sqrt) + \
                     kullback_leiblers.gauss_kl_white(self.u_gm, self.u_gs_sqrt)
        else:
            Kfmm = self.kernf.K(self.Zf) + tf.eye(
                self.num_inducing_f,
                dtype=float_type) * settings.numerics.jitter_level
            Kgmm = self.kerng.K(self.Zg) + tf.eye(
                self.num_inducing_g,
                dtype=float_type) * settings.numerics.jitter_level

            if self.q_diag:
                KL = kullback_leiblers.gauss_kl_diag(self.u_fm, self.u_fs_sqrt, Kfmm) + \
                     kullback_leiblers.gauss_kl_diag(self.u_gm, self.u_gs_sqrt, Kgmm)
            else:
                KL = kullback_leiblers.gauss_kl(self.u_fm, self.u_fs_sqrt, Kfmm) + \
                     kullback_leiblers.gauss_kl(self.u_gm, self.u_gs_sqrt, Kgmm)
        return KL
Ejemplo n.º 2
0
 def build_prior_KL(self):
     if self.whiten:
         if self.q_diag:
             KL = kullback_leiblers.gauss_kl_white_diag(
                 self.q_mu, self.q_sqrt)
         else:
             KL = kullback_leiblers.gauss_kl_white(self.q_mu, self.q_sqrt)
     else:
         K = self.kern.K(self.Z) + tf.eye(self.num_inducing,
                                          dtype=float_type) * settings.numerics.jitter_level
         if self.q_diag:
             KL = kullback_leiblers.gauss_kl_diag(self.q_mu, self.q_sqrt, K)
         else:
             KL = kullback_leiblers.gauss_kl(self.q_mu, self.q_sqrt, K)
     return KL
Ejemplo n.º 3
0
 def KL(self):
     return gauss_kl_white(self.q_mu, self.q_sqrt)
Ejemplo n.º 4
0
 def KL(self):
     all_mu = tf.concat([n.q_mu for n in self.nodes], 1)
     all_sqrt = tf.concat([n.q_sqrt for n in self.nodes], 2)
     return gauss_kl_white(all_mu, all_sqrt)