  This study considers the availability of room opportunities collected from a
Japanese hotel booking site. We empirically analyze the daily number of room
opportunities for four areas. To determine the migration trends of travelers,
we discuss a finite mixture of Poisson distributions and the EM-algorithm as
its parameter estimation method. We further propose a method to infer the
probability of opportunities existing for each observation. We characterize
demand-supply situations by means of relationship between the averaged room
prices and the probability of opportunity existing.
