Expected Goals, which is often symbolised as xG, is a measure of whether a given shot will result in a goal. This metric takes a number of variables into account, such as historical data, to give us an indication of how many goals a player or team should have scored based on the chances they had during a game, we spoke to InfoGol and they gave us some tips for expected goals & what we need to know. Here’s a guide to what expected goals are and how they’re calculated.
There are several variations of Expected Goals, including:
- Non-Penalty Expected Goals – the total expected goal minus any expected goals scored from penalty attempts
- Expected Goals For – the number of goals expected to have scored by a team based on their expected goals data.
- Expected Goals Against – the number of goals a team should have conceded, based on the data.
- Expected Goals Assisted – the number of assists a player should produce based on expected goals take from their passes.
- Expected Points – the total number of points a team is expected to win in correlation with the expected goals data.
Understanding Expected Goals
The highest value a single shot can be is 1, implying that a player has a 100% chance of scoring a goal. The higher the value of an Expected Goal, the more likely the player is to convert – an xG can be any number between 0 and 1. Non-penalty expected goals are particularly beneficial in providing a more accurate analysis, as penalties have an xG of 0.76 so they can distort the expected goals of a player or a team.
How is Expected Goals Calculated?
There are different models to use when measuring expected goalss, from the basic to the in-depth and complex. There are different variables taken into account when attempting to determine an expected goal, such as the distance from the goal, the passage of play, how the opportunity came into play, the angle of the shot and the shooting part. However, the more complex models also consider factors like the defensive play of the team’s opponents which makes the data more reliable.
Applying Expected Goals in Sports Betting
Expected goals are beneficial to sports bettors as it delivers additional information that the final score doesn’t always reflect. Because football is a typically low-scoring sport, the final score can be misleading – you might watch a team dominate the game, for example, but despite gaining more opportunities to score and have more possession, still manage to lose the overall game. This data won’t be representative of the game and therefore can’t really be used to build an opinion for future fixtures. But xG goals data can be used for future purposes to build a more reliable interpretation of the overall quality of a team and how they might perform in a match for placing more stable bets. Expected goals is a way of assigning a quality score to each team and player and as more data has been collected, the more reliable this metric is becoming. However, it’s important to remember that the analysis is not always completely representative and there are always anomalies in any situation.