We’ve seen a glimpse of what sports will be like without fans. We’ve seen that the lack of fans in the stands might significantly change outcomes of games.
As fans, we can sit back and see how empty stadiums affect games. Oddsmakers don’t have that luxury. They need to make assumptions now.
Point spreads and futures for the NFL season are already up at BetMGM, and there’s no way to definitively know how to handle the various possibilities. The NFL draws the most interest at sportsbooks, so a lot of money is riding on how oddsmakers adjust to the possibility of a season without fans.
The answer, at least for now, is there could be adjustment to NFL spreads, but not as much as you might think. And nothing yet.
How much of a difference will no fans mean to NFL lines?
The NFL Week 1 lines you see at BetMGM have not been adjusted for the possibility of empty or partially full stadiums. We have no idea what will happen in the fall, but the possibility of huge crowds for NFL games seems like a long shot. If you believe home-field advantage will be wiped out without fans, now might be the time to jump on some road teams for Week 1.
Home-field advantage is generally worth about 3 points on the point spread, though that can vary depending on the team. (The New Orleans Saints and Seattle Seahawks, for example, are historically very tough to play at home). If we get official word about empty stadiums for NFL games, you’re unlikely to see a huge shift in BetMGM’s point spreads right away.
“It probably makes a point or two difference,” said Jason Scott, the vice president of trading at Roar Digital, which runs BetMGM. “There might be more of an impact in college football. Someone like Drew Brees has played a long time, I’m not sure it affects those guys that have been around.”
Scott’s approach to home-field advantage, or lack of it this year, is something that analytics-based analysts have preached for a while: It’s not the crowd itself that makes a difference, it’s the crowd’s impact on the officials. Home teams generally get more calls. That theoretically changes if there’s no crowd to influence the refs.
“Positive affirmation does have some effect on officials,” Scott said. “If you look at leagues around the world, you see the impact crowds can have on calls for the home team. Officials are human. There’s an impact there.”
Scott also says routines will still help home teams, no matter if fans are allowed in. There’s a comfort level associated with not traveling. Scott believes that home-field advantage is lessened because officials aren’t hearing the crowd, but the home team still has some edge staying in a familiar routine. There’s just one issue.
“The question is quantifying that,” Scott said.
Nobody knows the answer. And that could actually help sportsbooks.
Could this NFL season be unpredictable?
Scott said he doesn’t think NFL games will be much different without fans. But he admitted there could be bigger shifts than usual to point spreads early in the season as trends develop, and the unusual offseason could create a chaotic season.
“I’m expecting a season advantageous to the bookmakers,” Scott said. “I think we’ll see more upsets. I think it won’t be as predictable.”
Casual bettors like favorites and familiar teams. More advanced bettors use statistical prediction models. Both may be thrown off in a season unlike any other we’ve experienced.
“Any randomness doesn’t hurt us,” Scott said.
Scott said he hasn’t adjusted future bets based on the possibility of home-field advantage being lessened, but it doesn’t matter much. BetMGM has seen less action than usual on future bets like NFL team win totals and Super Bowl odds because bettors are uncertain what the season will look like.
Scott said basketball would be affected most if there are empty stadiums or arenas, because fans are right on top of the action and have the biggest influence on officials. Scott thinks basketball lines could be adjusted three or four points if arenas are empty, taking away most or all of the home-court advantage.
Football is just behind basketball in terms of how empty stadiums could impact games. Baseball and hockey won’t see much difference if there are no crowds, Scott said.
Scott speaks authoritatively and his theories make sense. But he also knows that everything is an unknown.
“I could be wrong,” Scott said.
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