Home field advantage (or simply HFA) is an important point to consider when betting on team sports. Statistically speaking, clubs and franchises across most codes worldwide tend to perform best on their own patch; however, the effect or potency of home advantage is different from sport to sport, team to team, even referee to referee. So how do you work out the HFA in any given league or match-up, and how do you then apply it to online sports betting?
How to Calculate Home Field Advantage
There are two broad approaches you can take to quantify home field advantages in sport. One is to weigh up the home win/loss ratio, and the other is to compare how many goals, points, runs, etc. have been scored and conceded. To demonstrate these two methods, let’s use the 2013-14 Spanish Primera Division table:
Home Wins Percentage
Tally up all the results from the ‘Home’ section of the table, and you get 179 wins, 86 draws and 115 losses. On their own, those figures point to a significant advantage for the side in any given match – but how much, exactly?
First, add up the home wins and home losses and divide by two. So in this case: (179 + 115) / 2 = 147. This number represents the expected number of wins if there was no home advantage for any team.
Now, divide the total number of home wins by the expected number of win without HFA, like so: 179 / 147 = 1.22. This result tells us that in La Liga in 2013-14, home teams held a combined 22% edge over the visiting side.
Home Goals For & Against
The other basic method for deriving the HFA is to look at the scores for and against the home team. This is especially useful for Asian handicap betting, where knowing each side’s home and away stats is pivotal in determining whether a market’s odds are good value or not.
For example, let’s look at Atletico Madrid. Using the 2013-14 Liga table as a reference point, we see that Atleti scored 49 goals on home soil and conceded just 10. To calculate the capital club’s HFA, we use this formula:
Home field advantage = (Home goals for – home goals against) / games played
For Atletico’s 2013-14 form, we get (49 – 10) / 19 = 2.05. That means Diego Simeone’s troops held slightly better than a two-goal advantage whenever they played at the Vicente Calderon stadium.
You can also flip this formula to quantify a team’s performances away from home. Using Valencia’s 2013-14 record as an example, subtract the number of away goals conceded (29) from the number of away goals scored (16) and then divide by the number of league games played (19). Thus we get (16 – 29) / 19 = -0.68, a disadvantage of more than half a goal per game on the road.
Key Factors in HFA Betting
Loud crowds – Some home supporters are more vocal than your average fans, which in turn makes some opponents more difficult to visit than others. This is especially important to consider when Internet betting markets include teams which are traditionally strong at home regardless of form. For instance, despite finishing sixth or lower in every Premier League season between 2009 and 2013, Anfield’s fierce local support saw Liverpool lose no more than four home games in any of those failed campaigns.
Stadium size – Recent studies conducted at Harvard University suggest that for every 10,000 home fans at a game, the host side’s score advantage increases by 0.1 (or 10%). Thus, teams with greater stadium capacity tend to have a higher home advantage index than those which play at smaller venues.
Playing conditions – While sports like basketball and ice hockey are more or less uniform in terms of the dimensions and conditions of the playing area, this is not always the case in other codes. Cricket is notorious for the diversity of field sizes and pitch conditions from venue to venue and country to country – e.g. the flat dustbowls of India and the lively, grassy wickets of England provide each of those teams with a significant home edge in Test matches, especially when they face each other.
Quirky venues – Although sporting arenas are becoming more standardised in the modern professional era, there are plenty of stadia out there which provide unique challenges for visiting teams. The recently demolished HHH Metrodome in Minneapolis, for instance, was notorious for its Teflon-coated roof, which amplified crowd noise to alarming levels and brought about several visual and obstruction issues during Major League Baseball games.
Climate and geography – Some away trips are simply more gruelling than others, either due to local weather conditions or the sheer length of the journey. Both these factors can greatly favour the home side. Just ask the West Coast Eagles and the Fremantle Dockers from Perth, Australia, whose nearest AFL rivals (apart from each other) are based in Adelaide – more than 2000 km away.
Referees and umpires – No, we aren’t saying the refs are crooked. But the stats show that match officials tend to award more key decisions in favour of the home team than the visitors. This is especially the case with inexperienced referees and umpires, who often side with noisy home crowds. A 2011 Sports Illustrated report went so far as to claim that favourable officiating was the sole cause of home team advantage in American sports.
Best Home Win Records by League
Home field advantage applies to most team-oriented sporting competitions the world over, but some sides have made much better use of it than others. Let’s take a look at some of the more remarkable and interesting HFA stats from the top sports leagues around the globe.
English Premier League (EPL)
The UK’s top football division has boasted some of the game’s most impenetrable fortresses down the years. Liverpool were nigh-on untouchable at Anfield during the ’70s and ’80s, while Manchester United forged a reputation for scoring extra-time winners as a matter of course during Sir Alex Ferguson’s glorious 26-year reign at Old Trafford. But you can’t go past Chelsea, who went some 86 games unbeaten at Stamford Bridge in the Premier League between March 2004 and October 2008 – an English record.
National Football League (NFL)
As a traditional outdoor sport played all over the United States during the autumn and winter months, the NFL produces some of the most diverse climates you’ll see in a single sporting division – from the windy snow-swept fields of the Green Bay Packers and the Minnesota Vikings, to the warm tropical conditions that are home to the likes of the Tampa Bay Buccaneers. It is another Floridian franchise which holds the most impressive home streak in NFL history – the Miami Dolphins, who claimed an astonishing 31 consecutive victories (including playoffs) at the Orange Bowl between 1971 and 1974.
National Basketball Association (NBA)
For the best home performances in NBA history, it’s a tight call between the Boston Celtics of the mid-1980s and the famed 1990s Chicago Bulls side. Michael Jordan, Scotty Pippin and co. led the Bulls to a whopping 44 home wins on the trot at the United Center across two seasons in 1995 and 1996, while Larry Bird’s Celtics finished the 1985-86 campaign with 40 wins and a solitary defeat – aided, legend has it, by a worn-out parquet court at the Boston Gardens which bamboozled all comers with its inconsistent bounce.
ICC Test Championship
International cricket provides some of the clearest examples of how local conditions can help the home side and hinder the opposition. Sri Lanka and India are famously successful on native soil, yet they are ranked 6th and 7th respectively (out of 10 nations) for overall Test win percentage. Still, one cannot pass the all-conquering Australian sides of recent decades, with the Baggy Greens losing just two out of 54 home Tests between 1999 and 2008.
Australian Football League (AFL)
Speaking of the Aussies, we can’t help but mention the national football competition and its unique effect on HFA odds. Because the 10 teams from the state of Victoria all play home games at either the Melbourne Cricket Ground or Docklands Stadium, it is widely held that interstate teams like the Brisbane Lions, the Sydney Swans, Port Adelaide and especially West Coast and Fremantle hold the most significant home ground advantages. In fact, it is Geelong who rules the roost, the Cats having won 30 AFL home games in a row between 2008 and 2010 – many of those at Kardinia Park, the only remaining Victorian home ground outside the MCG and Docklands.