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HOW IS PROZONE USED TO FACILITATE REFEREE ANALYSIS

ProZone provides exact positioning when key incidents occur

1. Positioning

ProZone provides exact positioning when key incidents occur. This function covers every inch of the field for every second of the game so positioning can be monitored during incidents including:

• Awarding a foul
• Any Penalty Area incident, booking or red card offence (Critical Incidents)
• Corner Kicks
• Free kicks, including distance of the defensive wall from the ball.
• Offside Decisions
• Positioning Related to ‘Action Areas,’ including distance from the ball, and Assistant Referee positions
• Goals

Fouls

How far away is the referee from a player when he commits a foul? Is he to far away to make an informed decision? During the ninety minutes was the referee persistently to far away from play, or was he close to all the decisions he had to make? Before the introduction of ProZone all these questions could only be answered through the use of video tapes and subjective opinion. Now this can all be assessed accurately for the benefit of performance analysis.

Fig 2: Shows how ProZone identifies all fouls, including the position of the officials, the exact position on the field, and the timing.

From regular infringements to the pulling of a shirt, a handball or an obstruction, the ProZone System events every single foul in the game. At that point the system can show the position of the referee and the offending player. At the final whistle all infringements are logged so it can be assessed how far away the referee was when awarding fouls. This also creates a match average.

Fig 3: A table listing all the fouls and the distance of the referee from the incident. This provides match averages, which can be assessed.

This data can then be used to show a number of things.

• Was the referee keeping up with play?
• How did the referee perform against seasonal averages?
• It enables the referee to monitor his personal averages from game to game?
• With the graph showing what areas of the field the foul occurred we can also identify why the referee was a long distance from certain fouls, i.e. was the assistant closer for example?
• It is also possible to analyse how the referee’s positioning changed as the game went on. For example see the graph below

We can see here how the referee’s distances from fouls increased as the game went on. The green line (trend line) shows this steady increase in distance of the referee from fouls he awarded. The Red line (seasonal average) shows how much better his positioning was in the first half.

This data can then be used as a guide to analyse:

• Whether the referee was becoming fatigued
• Whether the games tempo increased,
• Or whether the referee just did not cover as much ground in the second half as in the first.

All these variables can then be used to coach the official for an improved performance in the following game. It is also helpful when the data can be presented in this manner rather than by a matter of opinion.

Critical Incidents

All referees, assistant referees, and fourth officials will be involved in controversial moments at some time. Penalty decisions, disallowed goals, red cards, dissent, simulation, reckless challenges and so on, are all quite simply part of the modern game and with the increases in TV coverage the pressures on the officials to get these critical decisions correct are more intense than ever.

Following all the replays of an incident on TV, with all the different angles, a referee and his coaches and assessors can make up their own minds as to whether the decision was correct or in-correct. Where ProZone can help in the analysis is to break down what factors could have affected the decision.

ProZone can not only highlight the position of the referee, (i.e. was he too far away or in some cases too close?), but also:

• If the referee was fatigued at the time. I.e. having just performed bouts of high intensity running.
• If the referee had his view obscured by other players
• The positioning of the referee’s assistants
• How the referee moved into position to give the decision, i.e. was the referee static and\or where had he moved from?

Corner Kicks

In addition to assessing the decision to award the corner kick a referee can also monitor his positioning. Quite often the TV coverage will not show the position of the referee so the overhead animation works to help a referee assess:

• Correct positioning for avoiding “active areas.”
• A good position for viewing infringements in the area and on the goal line.
• If the referee is static or on the move (ProZone’s speed function colour co-ordinates the speed of the referee at any given moment. A referee, who should not be static during a corner kick, is able to view whether they are standing still, walking or jogging at the time).
• If any defender is encroaching on the kick taker.

Include animation shot and average position graph (good & bad example, Poll & Beeby).

Free Kick Management

Again, in addition to assessing the decision to award the free kick, a referee can assess his free kick management. The overhead animation can be used to accurately assess the distance of the defensive wall, or player, from the ball. Again, this is not normally something that can be accurately assessed either by the naked eye at the game, or by just the TV coverage. Here ProZone allows the assessment of:

• The correct enforcement of 9.15m
• The positioning and mobility of the referee
• Not only a negative assessment, if the defensive wall is not 9.15m, but also a positive presentation of good wall management. For example a re-taken free kick showing the distance of the defensive wall before fig5 and after the re-take fig 6 (seen below).

Offsides

TV angles can sometimes be deceiving, and in the case of a replay not being available the accurate assessment of offside decisions would not be possible but for the use of the ProZone System. ProZone’s overhead animation allows the objective assessment of an offside decision. Even those that were not awarded, for example a close call leading up to a goal, can be looked at and analysed. The presentation of an offside clearly defines:

• If a player was in a offside position or not at the exact point the ball is played. ProZone presents this as a highlighted box around the player in an offside position fig 7. If the player was not offside, then no box would appear fig 8.
• The position of the referee and the assistant referee.

By using these functions a referee, his assistants, and assessors have a conclusive assessment of their decision.

Action Areas

As well as using the system to analyse performance surrounding certain events, the ProZone data can also be used to determine patterns of play in relation to referee movement. ProZone provides trained sports scientists who are skilled in analysing the data, who can then provide reports on referee movement and positioning.

Action zones, distance from the ball and movement profiles can all be used to further assess why a referee is too far away or too close to infringements, getting on top of play, becoming fatigued or working at high intensities. All these variables are closely related to the fitness data but here we shall concentrate on statistical data.

The referee’s distance from the ball can be taken as a match average and assessed against seasonal averages. But it can also be broken down into sections of the game to analyse what happened during that period. Questions can be asked such as Why was the referee further from play in the opening 20 minutes, and so close to play late in the second half when you would imagine fatigue to be setting in?

These questions can be answered by linking the stats to other variables such as action zones.

We can do the same for distance from fouls and provide suggestions as to why distances increase or decrease during certain periods of the game. These variables can also be compared to graphs showing the referees “movement profile.”

2. Fitness

The breadth of fitness information that ProZone can provide on a referee, and indeed any player, during a game is undoubtedly a highly critical tool in the analysis of performance, the monitoring and maintenance of physical fitness, and the scheduling of training sessions

Every inch of ground that a referee covers during a game is recorded by ProZone. This data can be used to analyse the referee’s:

• Work rate
• Freshness\sharpness
• Periods of fatigue and Recovery times
• Ability to working at high intensities during the correct periods of the game
• Ability to keep up with play
• Physical fitness in comparison with players

(See fitness section for ProZone stats on Referees)

All this data is presented in graph and table format making it easy for viewing and for further analysis.

All the data is collected by sports scientists and analysed for a physical assessment of the referees’ performance.

* HI Distance is the amount of ground covered at high speeds i.e. sprinting, and faster than normal running (high speed run) * Recovery time is the time in-between each high speed run. It indicates how long a referee needs to recover before being able to perform another sprint of HI run. * 1st v 2nd half HSR shows what percent increase, or decrease, the referee and the players had in their high speed running (HSR). The referee’s percent is displayed first, then the players’.

These stats can then be used to show:

• How the referee’s physical performance during the game, compared to the players,’ and a what tempo the game was played.
• How the referee performed compared to seasonal averages in areas such as high speed running, sprinting, and distance covered.
• If the referee increased and decreased his tempo in line with the demands of the match. The periods of play when the players’ tempo was at its lowest are exactly the same as when the referee’s intensity was lowest, which might indicate good awareness by the referee to have his recovery periods at the right time.
• How the referee adjusted to the changing tempos of the game.
• The endurance of the referee during periods of the game when fatigue will start taking affect and if the referee is able to perform at high intensities during these periods.
• How the referee’s distances from the ball and infringements relates to his intensities. It may be that the referee is becoming mentally fatigued, which might affect positional awareness.
• The referee’s recovery time, and how this related to the tempo of the
• The referee’s top speeds and the explosiveness of sprints performed, (i.e. from a standing start), which might help to highlight sharpness and freshness
• How both the referee’s and the players’ intensities changed across halves, and how they compare to each other.

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