Now there is evidence of an important effect in sports: "The home-field advantage, it turns out, is a sizable advantage. In a recent research report on the World Cup, Goldman Sachs (GS) calculated that the home-field advantage is worth 0.4 goals a game, which, in a sport heavy on 1-0 and 2-1 scores, is a huge factor."
And who does the crowd affect more, the team or the referee?: "The crowd does have an effect, but not necessarily on the team. A few social scientists have tried to look at the issue of home-field advantage empirically, and they’ve found that the crowd’s role in the phenomenon is that they sway the referees."
Article on http://ow.ly/y5lnz: