1. A recognition apparatus comprising: an acquiring unit configured to acquire positions of a particular part of a user in time series; a calculator configured to calculate a feature value of a motion of the particular part from the positions acquired in time series; a comparing unit configured to compare the feature value and a first threshold a recognizing unit configured to recognize the motion of the particular part using a first recognition method and a second recognition method which is different from the first recognition method; and a control unit configured to control the recognizing unit to select the first recognition method for recognizing a position or a motion of the particular part when the feature value is smaller than the first threshold, and select the second recognition method when the feature value is equal to or larger than the first threshold.