  Sentence specificity quantifies the level of detail in a sentence,
characterizing the organization of information in discourse. While this
information is useful for many downstream applications, specificity prediction
systems predict very coarse labels (binary or ternary) and are trained on and
tailored toward specific domains (e.g., news). The goal of this work is to
generalize specificity prediction to domains where no labeled data is available
and output more nuanced real-valued specificity ratings.
  We present an unsupervised domain adaptation system for sentence specificity
prediction, specifically designed to output real-valued estimates from binary
training labels. To calibrate the values of these predictions appropriately, we
regularize the posterior distribution of the labels towards a reference
distribution. We show that our framework generalizes well to three different
domains with 50%~68% mean absolute error reduction than the current
state-of-the-art system trained for news sentence specificity. We also
demonstrate the potential of our work in improving the quality and
informativeness of dialogue generation systems.
