Expected goals

[3][4][5] The expected goals metric is generally calculated by determining the likelihood of a shot being scored based on various factors, taken from the moment before the player shoots.

These factors may vary depending on the statistical model, but include the distance to the goal, angle, quality of the shot, and other characteristics.

Vic Barnett and his colleague Sarah Hilditch referred to "expected goals" in their 1993 paper that investigated the effects of artificial pitch (AP) surfaces on home team performance in association football in England.

[9] Jake Ensum, Richard Pollard and Samuel Taylor (2004) reported their study of data from 37 matches in the 2002 World Cup in which 930 shots and 93 goals were recorded.

[10] In a subsequent paper (2004), Ensum, Pollard and Taylor combined data from the 1986 and 2002 World Cup competitions to identify three significant factors that determined the success of a kicked shot: distance from the goal; angle from the goal; and whether or not the player taking the shot was at least 1 m away from the nearest defender.

He added: If we can establish this metric, we can then accurately and effectively increase our chances of scoring and therefore winning matches.

Similarly, we can use this data from a defensive perspective to limit the better chances by defending key areas of the pitch.

[17] In 2004, Alan Ryder shared a methodology for the study of the quality of an ice hockey shot on goal.

[3]The term 'expected goals' appeared in a paper about ice hockey performance presented by Brian Macdonald[4] at the MIT Sloan Sports Analytics Conference in 2012.

Macdonald's method for calculating expected goals was reported in the paper: We used data from the last four full NHL seasons.