Given the history of the game, the opponent has won two rounds, both of which involved them choosing paper. In round 1, they chose paper to beat my rock, and in round 4, they chose scissors to beat my paper. Since my last choice was rock, which resulted in a tie, I should try to exploit the pattern by assuming they might not choose rock again. Therefore, choosing scissors would be a good strategy because if the opponent chooses paper, scissors will beat it.