1. An information processing apparatus comprising: a computer including circuitry configured as a grouping unit that detects a part of an object from contents and performs grouping for each object based on each time the object appears in the content; a correlation degree calculating unit that calculates a correlation degree in time between all of the objects of which the grouping is performed by the grouping unit, the correlation degree including correlation between plural objects which alternately appear in time in the content without appearing at a same time in the content; and a display control unit that controls a display of a diagram of a correlation between the objects indicating the correlation in time between appearance of the objects in the content, based on the correlation degree between the objects which is calculated by the correlation degree calculating unit, wherein the correlation degree calculating unit includes an appearance section obtaining unit that obtains an appearance section of each object, a simultaneous appearance correlation degree calculating unit that calculates the correlation degree from a frequency where a plurality of objects appear at the same time, based on the appearance section of each object which is obtained by the appearance section obtaining unit and a transition appearance correlation degree calculating unit that calculates the correlation degree from a frequency where the plurality of objects appear by transiting in terms of time, based on the appearance section of each object which is obtained by the appearance section obtaining unit.