The analysis of short longitudinal series of circular data may be problematic and to
some extent has not been completely developed. In this paper we present a Bayesian
analysis of a model for such data. The model is based on a radial projection onto the
circle of a particular bivariate normal distribution. Inferences about the parameters of
the model are based on samples from the corresponding joint posterior density which
are obtained using a Metropolis-within-Gibbs scheme after the introduction of suitable
latent variables. The procedure is illustrated both using a simulated data set and a realdata
set previously analyzed in the literature
