A method for use in operation of a game apparatus includes obtaining a time series of samples containing information usable to determine activity of a plurality of predetermined objects used for controlling the game apparatus, processing the time series to determine whether one of the plurality of predetermined objects has been inactive during a game already in progress, and adding a new player to the game already in progress in response to a determination that one of the plurality of predetermined objects is currently active after determining that it was inactive. A system for use in operation of a game apparatus includes means for performing these steps.