Home advantage
In team sports, the term home advantage - also called home ground, home field, home court, home ice or defender's 'advantage' - describes the benefit that the home team is said to gain over the visiting team. This benefit has been attributed to psychological effects supporting fans have on the competitors or referees; to psychological or physiological advantages of playing near home in familiar situations; to the disadvantages away teams suffer from changing time zones or climates, or from the rigors of travel; and in some sports, to specific rules that favor the home team directly or indirectly. In baseball and cricket in particular, the difference may also be the result of the home team having been assembled to take advantage of the idiosyncrasies of the home ballpark/ground, such as the distances to the outfield walls/boundaries; most other sports are played in standardized venues.
The term is also widely used in "best-of" playoff formats as being given to the team that is scheduled to play one more game at home than their opponent if all necessary games are played.
In many sports, such designations may also apply to games played at a neutral site, as the rules of various sports make different provisions for home and visiting teams. In baseball, for instance, the visiting team always bats first in each inning. Therefore, one team must be chosen to be the "visitor" when games are played at neither team's home field. Likewise, there are uncommon instances in which a team playing a game at their home venue is officially the visiting team, and their opponent officially the home team, such as when a game originally scheduled to play at one venue must be postponed and is later resumed at the other team's venue.
Advantages
In most team sports, the home or hosting team is considered to have a significant advantage over the away or visiting team. Due to this, many important games in many sports have special rules for determining what match is played where. In association football, matches with two legs, one game played in each team's "home", are common, with the team hosting the second leg having this home-field advantage. It is also common to hold important games, such as the Super Bowl, at a neutral site in which the location is determined years in advance. In many team sports in North America, playoff series are often held with a nearly equal number of games at each team's site. However, as it is usually beneficial to have an odd number of matches in a series, the final home game is often awarded to the team that had more success over the regular season.An example is UEFA Champions League, UEFA Europa League and UEFA Europa Conference League home and away legs, with weaker teams often beating the favorites when playing at home. The World Cup victories of Uruguay, Italy, England, Germany, Argentina and France are all in part attributed to the fact that the World Cup was held in the winner's country. A 2006 study by The Times found that in the English Premiership, a home team can be expected to score 37.29% more goals than the away team, though this changes depending on the quality of the teams involved. Others have suggested that the increase in British medals during the 2012 Olympics may have been impacted by home court advantage.
The strength of the home advantage varies for different sports, regions, seasons, and divisions. For all sports, it seems to be strongest in the early period after the creation of a new league. The effect seems to have become somewhat weaker in some sports in recent decades.
Richard Adams and Susan Kupper described home-field advantage as an expertise deficiency. They demonstrated that, in theory and in practice, home-field advantage decreases as superiority of performance increases. They also showed that home-field advantage is not applicable for no-hit major league baseball games for pitchers who either replicated performance by winning two or more no-hitters or amassed a large number of career wins. Their general finding was that home-field advantage is a metric for the inability to maintain performance independent of environment and that this metric is inversely related to variables of expertise.
In recognition of the difficulty in winning away matches, cup competitions in association football often invoke the away goals rule. Away goals can also sometimes be used to separate teams level on points and goal difference in league competitions.
Causes
Factors related to the location and the venue
There are many causes that attribute to home advantage, such as crowd involvement, travel considerations, and environmental factors. The most commonly cited factors of home advantage are usually factors which are difficult to measure and so even their existence is debated. Most of these are psychological in nature: the home teams are familiar with the playing venue, they can stay in their homes rather than a hotel, they don’t have to travel as far before the game, and they have the psychological support of the home fans.Other factors, however, are easier to detect and can have noticeable effects on the outcome of the game. In American football, for instance, the crowd often makes as much noise as it can when the visiting team is about to run a play. That can make it very difficult for the visiting team's quarterback to call audible play changes, or for any player to hear the snap count. In contrast, the crowd is often quiet while the home team is on offense, and that enables the quarterback to use the hard count intended to draw the defense offsides as the defense can hear the hard count. In basketball, when a visiting player is making a free throw, home fans behind the backboard typically wave their arms or other objects in an attempt to break the visiting player's focus on making the shot. Environmental factors such as weather and altitude are easy to measure, yet their effects are debatable. Both teams have to play in the same conditions, but the home team may be more acclimated to local conditions with difficult environments, including extreme temperatures and high altitude.
The stadium or arena will typically be filled with home supporters, who are sometimes described as being as valuable as an extra player for the home team. The home fans can sometimes create a psychological lift by cheering loudly for their team when good things happen in the game. The home crowd can also intimidate visiting players by booing, whistling, or heckling. Generally the home fans vastly outnumber the visiting team's supporters. While some visiting fans may travel to attend the game, home team fans will generally have better access to tickets and easier transport to the event, thus in most cases they outnumber the visitors' fans. In some sports, such as association football, sections of the stadium will be reserved for supporters of one team or the other but the home team's fans will have the bulk of the seating available to them. In addition, stadium/arena light shows, sound effects, fireworks, cheerleaders, and other means to enliven the crowd will be in support of the home team. Stadium announcers in many sports will emphasize the home team's goals and lineup to excite the crowd.
Ryan Boyko, a research assistant in the Department of Psychology in the Faculty of Arts and Sciences at Harvard University, studied 5,000 English Premier League games from 1992 to 2006, to discern any officiating bias and the influence of home crowds. The data was published in the Journal of Sports Sciences and suggested that for every additional 10,000 people attending, home team advantage increased by 0.1 goals. Additionally, his study found that home teams are likely to be awarded more penalty kicks, and this is more likely with inexperienced referees.
Further, home players can be accustomed to peculiar environmental conditions of their home area. The city of Denver, being above sea level, has thinner air, enough so that it affects the stamina of athletes whose bodies are not used to it. Although baseball is less aerobically demanding than many other sports, high altitude affects that sport's game play in several important ways. Denver's combination of altitude and a semi-arid climate allows fly balls to travel about 10% farther than at sea level, and also slightly reduces the ability of a pitcher to throw an effective breaking ball. The low humidity also causes baseballs to dry out, making it harder for pitchers to grip them and further reducing their ability to throw breaking balls. The Colorado Rockies have a very large home advantage. This anomaly has been countered with Colorado's innovative use of humidors to keep the baseballs from drying out. Denver's altitude advantage has also come into play in gridiron football; the second longest field goal in National Football League history took place in Denver, as did the longest recorded punt. The national association football team of Bolivia also enjoys the advantage of playing at high altitude: at home during World Cup qualifiers at the even more extreme 3,600 m altitude of La Paz they have even been known to beat Brazil, a team regularly ranked number one in the FIFA World Rankings. At another game played in Bolivia, Bolivia beat Argentina, who were ranked sixth in the world, 6–1 on April 1, 2009, Argentina's heaviest defeat since 1958. In cricket, the condition of the pitch and the behaviour of the ball when it bounces off the pitch varies significantly in different parts of the world, and consequently the players on the visiting team must adjust to the ball behaving in an unfamiliar way to be successful on foreign surfaces; additionally, the home team has the right to adjust the preparation of its pitches in a manner which specifically enhances its own strengths or exacerbates its opponent's weaknesses.
The weather can also play a major factor. For example, the February average temperature minimum in Tel Aviv, Israel is, while the average at the same time in Kazan, Russia is, with snow being common. This means that when Rubin Kazan played at home to Hapoel Tel Aviv in the 2009-10 UEFA Europa League, Hapoel needed to acclimatize and were therefore at a disadvantage. Hapoel duly lost the match 3–0. However, a home stadium subject to frequent inclement weather can be a burden on the home team: the Buffalo Bills, whose home stadium is subject to high and unpredictable winds and lake-effect snow in the late fall and early winter, regularly suffer large numbers of injuries late in the season and the Bills have had to cancel practice due to the weather. A study, published in the Orthopedic Journal of Sports Medicine and reported by Forbes in 2016, analyzed NFL injury reports from 2012-2014 and found that players had a two-fold greater risk of concussions and a 1.5 times greater risk of ankle injuries in games played at or colder compared to games at or warmer.
Sometimes the unique attributes of a stadium create a home-field advantage. The unique off-white Teflon-coated roof of the Hubert H. Humphrey Metrodome trapped and reflected noise to such an extent that it was distracting or even harmful. This, combined with the color of the roof, caused opposing baseball players to commit more errors in the Dome than in other ballparks. While this is no longer an issue for opponents of the Minnesota Twins with that team's 2010 move to the open-air Target Field, it remained important to the many college baseball teams that played games in the Dome until its late 2013 closing. Hard Rock Stadium, the home stadium of the NFL's Miami Dolphins, is designed in such a way that when the sun is overhead, the home sideline is in the shade while the visitors sideline is directly in the sun's path. This, combined with the hot tropical climate South Florida receives, can lead to differences of up to or more between the two sidelines, with the visiting sideline temperature getting as high as 120 °F. The parquet floor at the Boston Celtics' former home of Boston Garden contained many defects, which were said to give the Celtics, who were more likely to be familiar with the playing surface, an advantage. During the 1985–1986 season, the Larry Bird-led Celtics posted a home court record of 40–1; this record still stands in the NBA. Memorial Gymnasium, the venue for men's and women's basketball at Vanderbilt University, was built in 1952 with the team benches at the ends of the court instead of along one of the sidelines, a setup that was not unusual at the time. However, the configuration is now unique in U.S. major-college sports, and has been said to give the Commodores an edge because opposing coaches are not used to directing their teams from the baseline. Cherry Hill Arena, a New Jersey–based arena in the southern suburbs of Philadelphia, had a number of idiosyncrasies that its home teams used to their advantage but earned the arena an extremely poor reputation, including a slanted ice surface that forced opponents to skate the majority of the game uphill and lack of showers for the visiting team.
Sports Illustrated, in a 17 January 2011 article, reported that home crowds, rigor of travel for visiting teams, scheduling, and unique home field characteristics, were not factors in giving home teams an advantage. The journal concluded that it was favorable treatment by game officials and referees that conferred advantages on home teams. They stated that sports officials are unwittingly and psychologically influenced by home crowds and the influence is significant enough to affect the outcomes of sporting events in favor of the home team.
Other research has found that crowd support, travel fatigue, geographical distance, pitch familiarity, and referee bias do not have a strong effect when each factor is considered alone suggesting that it is the combination of several different factors that creates the overall home advantage effect. An evolutionary psychology explanation for the home advantage effect refers to observed behavioral and physiological responses in animals when they are defending their home territory against intruders. This causes a rise in aggression and testosterone levels in the defenders. A similar effect has been observed in football with testosterone levels being significantly higher in home games than in away games. Goalkeepers, the last line of defense, have particularly strong testosterone changes when playing against a bitter rival as compared to a training season. How testosterone may influence results is unclear but may include cognitive effects such as motivation and physiological effects such as reaction time.
An extreme example of home advantage was the 2013 Nigeria Premier League; each of the 20 teams lost at most 3 of 19 home matches and won at most 3 of 19 away matches. Paul Doyle ascribed this to visiting teams' facing "violent crowds, questionable refereeing and rriving just before kick-off after long road trips, often on hazardous surfaces".
The 2020–21 NHL season saw major disruption due to COVID-19-restricted conditions that resulted in bubble playoffs and ghost games, as fans were unable to attend in person. New research has shown that this led to a significant drop to home advantage compared with the previous six seasons. In 592 games played under the restricted conditions through March, home teams suffered a decline of 10% while road teams’ win rates increased by 7%.