Collectively predicting input operations for plural operation object items (subwindows) belonging to a same window. A proposal window PG stores in a statistics information database and manages information about the input entity and an operation object of an input operation accepted from a user, and a window to which the operation object belongs, along with transition information indicating the transition of active windows concerned in previous input operations. When an active window transitions because of an input operation accepted from the user, it searches the statistics information database for information that contains information about a new active window and is associated with transition information matching the transition of active windows concerned in previous input operations.