Abstract: A server device includes the following elements. A random selection section randomly selects a game content having a certain attribute on the basis of a predetermined winning probability. A progress processor progresses a game and calculates a progress rate of the game on the basis of a predetermined parameter. A winning probability changing processor changes, according to the attribute and a progress rate of the game calculated at a certain time point, winning probabilities of game contents after the lapse of a predetermined period from the certain time point, and sets, according to the attribute, an interval at which the winning probabilities of the game contents are changed and also sets attributes so that the attribute for which the winning probability of a corresponding game content is changed will periodically vary. A providing section provides a selected game content to the game player.