Provided is a classification device that is capable of classifying time-series data of position information into groups wherein the continuity of times associated with the position information is guaranteed. The classification device (100) is provided with: a data recording unit (110) for recording a plurality of time information and a plurality of position information respectively corresponding to the plurality of time information; a rearrangement unit (120) that rearranges the plurality of position information in chronological order using the plurality of time information; a hidden Markov model recording unit (130) that records a left-to-right hidden Markov model having undefined parameters and having a plurality of states; a Markov model output unit (140) that determines the parameters by inputting the chronologically arranged plurality of position information into the hidden Markov model; and a classification unit (150) that classifies each of the plurality of position information into one of the plurality of states by inputting the chronologically arranged plurality of position information into the hidden Markov model having determined parameters.
