Looking at the opponent's pattern, they've never chosen paper in the previous 7 rounds, favoring scissors (4 times) and rock (3 times). There seems to be a loose alternating pattern between rock and scissors, with the opponent playing scissors in round 7. Following this pattern, they might play rock in round 8. Additionally, since I'm ahead 3-1, I can afford to take a calculated risk. Paper beats rock, so this seems like a strategic choice based on the opponent's historical preferences.