  In this paper, we consider a novel machine learning problem, that is,
learning a classifier from noisy label distributions. In this problem, each
instance with a feature vector belongs to at least one group. Then, instead of
the true label of each instance, we observe the label distribution of the
instances associated with a group, where the label distribution is distorted by
an unknown noise. Our goals are to (1) estimate the true label of each
instance, and (2) learn a classifier that predicts the true label of a new
instance. We propose a probabilistic model that considers true label
distributions of groups and parameters that represent the noise as hidden
variables. The model can be learned based on a variational Bayesian method. In
numerical experiments, we show that the proposed model outperforms existing
methods in terms of the estimation of the true labels of instances.
