Step-by-step explanation:
There are other factors than Roberto coming that could have affected the outcome of the game. For example, maybe the night games were against better teams to generate better ratings in prime time. Moreover, maybe the Angels do better at home due to home-field advantage. There are many factors such as these that could explain why Roberto witnessed such a high win rate at the games he went to, so it cannot be concluded that Roberto's attendance caused the Angels to win.