Polycrystalline materials, such as metals, are composed of heterogeneously oriented crystals. Observed crystal orientations modelled a sample from an orientation distribution function (ODF), which determines variety material properties and is therefore great interest to practitioners. Observations consist quaternions, four-dimensional unit vectors reflecting both rotation single crystal. Thus, ...

We review three algorithms for Latent Dirichlet Allocation (LDA). Two of them are variational inference algorithms: Variational Bayesian inference and Online Variational Bayesian inference and one is Markov Chain Monte Carlo (MCMC) algorithm – Collapsed Gibbs sampling. We compare their time complexity and performance. We find that online variational Bayesian inference is the fastest algorithm a...