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home field advantage

The home environment in professional sport, including American football, has long been considered a key factorinfluencing match outcomes. Home field advantage is commonly attributed to several main factors, such as fan support, familiar playing conditions, the absence of travel-related stress, and in some cases unintentional referee bias. In the NFL, it has been historically documented that teams achieve a higher winning percentage in home games than in away games, although the magnitude of this effect may vary across individual seasons.

The main research question of this article is:
“Do teams in the AFC have a higher probability of winning home games than away games?”This question is analyzed through a statistical examination of the results from the 2024 regular season. Average points scored and points allowed in home and away games are compared, along with their effect on the probability of winning.
Home field advantage in the NFL is not fixed. Its impact may vary depending on factors such as team quality, playing strategy, stadium-specific characteristics, or coaching decision-making styles. It is therefore essential to determine whether the 2024 season confirms traditional patterns of home advantage or suggests a shift in its importance.
Home advantage is a phenomenon that has been extensively studied across various sports disciplines, including American football. Research indicates that home teams win more frequently than visiting teams, with this effect usually attributed to several key factors.Key factors influencing home advantage
One of the most frequently cited factors is home crowd support. Fans can positively influence home team players by providing energy and motivation (Nevill & Holder, 1999). At the same time, they may exert psychological pressure on referees and influence their decisions in favor of the home team (Anderson et al., 2012).
In the NFL, some stadiums are famous for their noise levels, such as Arrowhead Stadium, the home of the Kansas City Chiefs, where crowd noise often exceeds 100 decibels. This noise can disrupt the opposing team’s communication, particularly during offensive plays.
Home teams are accustomed to the conditions of their stadium, including the type of playing surface, climate, and lighting conditions (Pollard, 2006). This can play a crucial role, especially in cases where teams from warmer regions must adapt to games played in colder climates and vice versa.
For example, teams such as the Buffalo Bills or the New England Patriots are accustomed to playing in cold weather, which may give them an advantage over teams from warmer regions such as the Miami Dolphins or the Jacksonville Jaguars.
Visiting teams often have to overcome long travel distances, which can negatively affect their performance. Research has shown that traveling across multiple time zones can lead to jet lag, which negatively affects both physical performance and mental concentration (Smith et al., 1997).
The NFL is specific in that it includes teams spread across the entire United States, meaning that some teams must travel thousands of kilometers between games. For example, the Seattle Seahawks, based in the northwestern United States, often face the longest travel distances of all NFL teams.
Another factor that may influence home advantage is subconscious cognitive bias among referees. Research shows that referees often subconsciously favor home teams, especially in borderline situations (Balmer et al., 2007).
Analyses of penalty decisions in the NFL suggest that home teams tend to receive fewer penalties than visiting teams, although this effect has slightly decreased in recent years due to the introduction of video review systems.
According to a study by Jamieson (2010), the average level of home advantage in the NFL is around 55–60 percent home team victories. However, this trend has shown a slight decline over recent decades.
This article focuses on analyzing the impact of the home environment on wins by teams in the AFC conference during the 2024 regular season. The main objective is to determine whether home teams have a higher probability of winning compared to away games.The data used for this analysis come from official results of the 2024 NFL regular season. The sample includes all teams from the AFC conference, and the following statistics were recorded:
-Number of home wins and losses – the total number of games won at the home stadium.
-Number of away wins and losses – the total number of games won on the opponent’s field.
-Average points scored at home – the average number of points scored by a team in home games.
-Average points scored away – the average number of points scored by a team in away games.
-Average points allowed at home – the average number of points allowed by a team in home games.
-Average points allowed away – the average number of points allowed by a team in away games.
-Percentage probability of winning at home – the percentage chance of winning home games.
-Percentage probability of winning away – the percentage chance of winning away games.Statistical method used
Descriptive statistics and regression analysis were used for the analysis. The model evaluates the relationship between points scored and points allowed and the probability of winning.
In addition to regression analysis, differences between home and away winning probabilities are also presented.
Based on previous research and theoretical insights, the following results are expected:
Teams should exhibit a higher percentage probability of winning at home than away, which would confirm the hypothesis of home field advantage.

The average values of individual variables show that:
Teams score more points at home than away, suggesting that offensive performance is stronger in the home environment.
Teams allow fewer points at home than away, which may indicate that defense is more effective at home or that visiting teams struggle to adapt to new conditions.
The probability of winning at home is higher than away, confirming the existence of home field advantage.

Table 1: Regression analysis of factors influencing home team wins

Table 2: Regression analysis of factors influencing home team wins

Table 5: Regression analysis of factors influencing away team wins

Table 6: Effect of points scored on winning

Points scored away have a greater impact on winning than points scored at home.

Table 7: Effect of points allowed on winning

Points allowed home have a stronger negative effect on winning at home than away.

Teams score more points at home on average than away, while also having stronger defensive performance.
The probability of winning at home is higher (63.2 percent) than away (43.8 percent), confirming the home advantage hypothesis.
Points scored away have a greater impact on winning than points scored at home, suggesting that successful teams need to excel even in games played outside their home stadium.
Points allowed have a negative effect on winning both at home and away, but this effect is slightly stronger at the home stadium.
Overall, the models confirm that home advantage exists, but its effect may be smaller than expected, particularly for elite teams that perform consistently well away from home.
The analysis shows that points allowed have a greater negative impact on the probability of winning at home than away. This means that when a home team concedes points, its chance of winning decreases more than that of a visiting team in a comparable situation.This effect can be explained by several factors:
The home team faces greater pressure from fans who expect a victory. When the home team allows points, demoralization may occur, which affects on-field performance.
Coaches of home teams may be under pressure to respond quickly and adjust strategy, leading to greater risk-taking. Some teams adopt more aggressive play after conceding points, which can result in additional mistakes.
If a home team concedes, its probability of winning decreases by an average of 25 percent. For away teams, the decrease is smaller, averaging 22.7 percent.
These results suggest that the psychological effect of the home environment may in certain situations be more negative than positive, particularly when a team finds itself in a disadvantageous position. These findings offer a new perspective on the traditional concept of home advantage and indicate that the pressure associated with home games can be counterproductive for some teams.Although the analysis provides valuable insights into home advantage in the NFL, it is important to consider certain limitations.
Limitation to the 2024 regular season. The results apply only to this season and may not be fully generalizable to other seasons. Home advantage may change over time depending on league trends, rule changes, or competitive balance.
Individual team performance was not taken into account. The analysis worked with overall trends within the AFC conference, but specific teams may exhibit different patterns, for example some teams may have an extremely strong home record, while others may perform similarly at home and away, as well as differences driven by schedule strength.
This article confirmed that the home environment provides teams in the AFC conference with an advantage during the 2024 regular season, while also revealing several surprising nuances. While home teams show a higher probability of winning and better offensive and defensive statistics, points scored away play a more significant role in victories than points scored at home. In addition, psychological pressure after conceding points is greater for home teams, which may be an important factor in game strategy planning.References
ANDERSON, Eric, et al. (2012). Home Advantage in Professional Sports: A Meta-Analysis. Journal of Sports Science and Medicine
BALMER, Nigel J., et al. (2007). Influence of Crowd Noise on Refereeing Decisions in Association Football. Journal of Sports Sciences
JAMIESON, John P. (2010). The Home Field Advantage in Athletics: A Meta-Analysis. Psychology of Sport and Exercise
NEVILL, Alan M., & HOLDER, Russell L. (1999). Home Advantage in Sport: An Overview of Studies on the Advantage of Playing at Home. Sports Medicine
POLLARD, Richard. (2006). Home Advantage in Soccer: Variations in its Magnitude and a Literature Review on Inter-Related Factors. Journal of Sports Sciences
SMITH, R. S., & REILLY, Thomas. (1997). Influence of Travel on Performance in Sport: Implications for Performance and Recovery. Sports Medicine
NFL.COM (2024). Team Stats – NFL Statistics. [online]. Available at: https://www.nfl.com/stats/team-stats/LIVESPORT.CZ (2024). NFL – Results and statistics. [online]. Available at: https://www.livesport.cz/americky-fotbal/usa/nfl/

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How to Visualize Data the Right Way part 1

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How to Visualize Data the Right Way part 2

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