Glossary

There are three types of data element captured or calculated.

Data Element Type	Definition
Action Event	An action captured during the game. The most granular level of data collected.
Action Event Metadata	Describes an Action Event – provides further context or detail to an in-game action
Metric	A derived element calculated from Action Events and Game Meta Events.

I collect my own data and do not use any external sources. However, I try and align to the data definitions provided by Opta. To avoid a change control nightmare, where an Opta definition is used, I provide the link to it. (Opta Definitions).

Action Events (All Celtic Players)

The following is collected or every Celtic player individually for every match.

It is collected at the Team level for the opposition.

For every data element, I record whether Celtic maintained possession because of this action, or lost it.

Data Element	Definition
Completed Pass / Incomplete Pass	Opta Event Definitions – Stats Perform
Set Piece Completed Pass / Incomplete Pass	A Completed / Incomplete Pass from a throw in, corner or free kick.
Throw In Completed Pass / Incomplete Pass	A Completed / Incomplete from a throw in.
Corner Completed Pass / Incomplete Pass	A Completed / Incomplete from a corner kick.
Free Kick Completed Pass / Incomplete Pass	A Completed / Incomplete from a free kick.
Clearance	Opta Event Definitions – Stats Perform
Tackle Won & Possession Won	An attempt to win the ball using feet or body where the challenge is won and ball possession maintained.
Tackle Lost & Possession Won	An attempt to win the ball using feet or body where the challenge is lost but ball possession is maintained. For example, a Celtic player is challenged, loses the challenge but the ball deflects to another Celtic player.
Tackle Won & Possession Lost	An attempt to win the ball using feet or body where the challenge is won but the ball goes to the opposition.
Tackle Lost & Possession Lost	An attempt to win the ball using feet or body where the challenge is lost and the ball possession goes to the opposition.
Aerial Challenge Won & Possession Won	An attempt to win the ball using the head where the challenge is won and ball possession maintained.
Aerial Challenge Lost & Possession Won	An attempt to win the ball the head where the challenge is not won but ball possession is maintained. For example, a Celtic player is challenged, loses the challenge, but the ball deflects to another Celtic player.
Aerial Challenge Won & Possession Lost	An attempt to win the ball using the head where the challenge is won but the ball possession goes to the opposition.
Aerial Challenge Lost & Possession Lost	An attempt to win the ball using the head where the challenge is lost and the ball possession goes to the opposition.
Interception	Opta Event Definitions – Stats Perform
Deflection	The ball unintentionally hits a player.
Block Cross	An attempt to play the ball into the penalty box from wide is stopped or deflected intentionally.
Shield Out	Opta Event Definitions – Stats Perform – called “Shield ball out of play”.
Suffer Foul	Opta Event Definitions – Stats Perform – called “Foul won”. I do award a Suffer Foul to the player disadvantaged in the event of a handball.
Miss Tackle	An attempt at a foot or body-based tackle that fails to challenge the opposition player.
Miss Block Cross	An attempt to stop a pass or speculative ball played from wide into the penalty area that fails to stop the ball.
Miss Control	The player loses possession by failing to maintain the ball under minimal pressure (i.e. isn’t challenged).
Dribble Past	An instance where a player is run past by an opponent with the ball.
Commit Foul	Opta Event Definitions – Stats Perform – called “Foul conceded”.
Progressive Run	A forward run with the ball that does not take any opponents out the game but progresses the ball either: 30 metres from the defensive half to the opposition half or 10 metres inside the opposition half
Minutes Played	Number of minutes player is on the pitch.

Action Events (Goalkeeper)

The following is collected for every Celtic Goalkeeper for every match. I do not collect Goalkeeper specific data for the opposition. I simply couldn’t be bothered to go that far!

For every data element, I record whether Celtic maintained possession because of this action, or lost it.

Data Element	Definition
Save Pushed Wide	Shot kept out the goal by the goalkeeper sending the ball wide of the goal.
Save Caught	Shot kept out of the goal by the goalkeeper catching the ball.
Save Parried	Shot kept out of the goal by the goalkeeper blocking the shot with his hands, and the ball rebounding forward.
Save Fumble	Shot kept out of the goal with an attempt to catch it, but the goalkeeper loses control of the ball.
Save Punched	Shot kept out of the goal by the goalkeeper using his fists to punch the ball away.
Save Tip Over	Shot kept out the goal by the goalkeeper tipping the ball over the bar.
Save Foot	Shot kept out of the goal by the goalkeeper using his legs to deflect the ball.
Cross Catch	An attempted pass or speculative pass across the penalty box that the goalkeeper takes control of with his hands.
Miss Cross	An attempted pass or speculative pass across the penalty box that the goalkeeper attempts to take control of with his hands but fails.

Game Meta Event (All Celtic Players)

The following are data elements that add further context and description of Action Events. They are collected for every Celtic player for every match and at the Team level for the opposition.

Data Element	Definition
Recovery	Opta Event Definitions – Stats Perform – called “Recovery”
Cross Success	A pass or speculative ball played from wide into the penalty area that successfully reaches a player from your side.
Defensive Save	An action taken that avoids, with high probability (judgement call) an opposition goal or Big Chance.
Possession in Box	Records each instance where the player has control of the ball within the opposition penalty area.
Danger Zone Pass	A completed pass that leaves a player in possession in the area the width of the 6 yard box, and between the opposition goal and 18 yard line.
Defensive Third Win	The ball is won back in the players’ defensive third of the pitch
Final Third Win	The ball is won back in the oppositions defensive third of the pitch
Defensive Error	An action that leads directly to the opposition having a shot at goal, or high probability of doing so.
Defensive Critical Error	An action leading directly to the opposition having a Big Chance or high probability of getting a shot on target.
Defensive Third Loss	Lose possession in your own team’s defensive third of the pitch.
Final Third Loss	Lose possession in the opposition’s defensive third of the pitch.
Chance Attempt Fail	A pass that is intended to directly provide a scoring chance but fails to be completed.
Dribble Fail	An attempt at a take on, to go past an opponent, that results in being successfully challenged or losing control of the ball.
Cross Fail	A pass or speculative ball played from wide into the penalty area that does not reache a player from your side.
Offside	Opta Event Definitions – Stats Perform
Yellow Card	Player cautioned.
Red Card	Player sent off.

Shot, Goal, Assist and Chance Data

For every shot attempted, the following may be captured depending on the nature of the shot or chance. The following data is collected both for Celtic and all opponents at the player level.

Data Element	Definition
Minute	The minute of the game in which the shot occurred.
Score	The game score when the shot was taken.
Shooter	Name of player taking the shot.
Team	Team the Shooter plays for.
Zone	The area of the pitch the shot is taken from. 1 – 6 or penalty according to the below shot chart.

With thanks to American Soccer Analysis

Shot Result	Whether the shot was on target, off target or blocked. http://optasports.com/news-area/blog-optas-event-definitions.aspx
Shot Type	Shot taken with Right or Left foot, or Head.
Goal Type	Goal from open play or Penalty.
xG (Team)	The Expected Goal value assigned to the team for every shot.
xNPG	The Expected Goal Value assigned to the shooter for every non-penalty shot.
xPts	The Expected Points gained because of a goal, where winning every game is assumed to be worth 3 points.
Big Chance	Opta Event Definitions – Stats Perform
Key Passer	The player providing the pass before the shot. Key Pass defined here Opta Event Definitions – Stats Perform
Pass Type	Indicates whether the pass resulting in the shot came from open play, a corner or a free kick.
Assister	I follow the Opta definition of a Fantasy Goal Assist Opta Event Definitions – Stats Perform.  This field holds the name of the player awarded the assist.
xA	Expected Assist. The probability of a goal being scored from any shot taken from the position the passer provided a pass to.
Blocker	The name of the player who blocks a shot.
Keeper	The name of the keeper saving a shot.
Penalty Conceder	The name of the player conceding a penalty.
Defensive Error	The name of the player who committed a defensive error resulting on a shot.
Defensive Error xG	The xG value of the shot resulting from a defensive error. This is assigned to the player making the error.
Own Goal	The name of the player conceding an own goal.
Own Goal Team	The team conceding the own goal.
In Box	Whether the shot was taken inside or outside the penalty box.
Secondary Assister	The player providing the pass before the pass that set up the chance.
Secondary Assist xA	The xA value assigned to the pass that set up the chance, assigned to the passer prior.

Packing and Impect Data

For a full description of Packing and Impect please read Concerning “Packing”. The following data is collected both for Celtic and all opponents.

Data Element	Definition
Passer	The name of the player providing a pass that has taken out at least one opponent.
Receiver	The name of the player receiving and controlling the pass which has taken out at least one opponent.
Dribbler	The name of the player taking out opponents by dribbling the ball past them.
Defenders Packed	The number of defenders from the opposition bypassed.
Midfielders Packed	The number of midfielders from the opposition bypassed.
Forwards Packed	The number of forwards from the opposition bypassed.
Packing Rate	The number of opposition players bypassed from the pass or dribble.
Impect Score	The points assigned for each Pack event: 3 points per defender packed 2 points per midfielder 1 point per forward.
Packed	The number of times a player is taken out the game by an opposition pass or dribble.
Pack Pass Chances	The number of shots created from passes that were Pack Passes.
Pack Pass xA	The expected assist value of the chances created from Pack Passes.

Player Metrics

The following are derived values calculated per Celtic player per game, and at the Team level for the opposition. Many are also calculated at Team level.

Data Element	Definition
Possessions Won	The sum of: Tackles Aerial Challenges Intercepts Blocked Crosses Shield Outs where possession was won for your team.
Challenges Won	The sum of: Tackles Aerial Challenges Intercepts Blocked Crosses Shield Outs Blocked Shots won irrespective of which team then got possession.
Dispossessed	The sum of Tackles and Aerial Challenges lost outright plus the number of Miss Controls.
Unsuccessful Challenges	The sum of: Tackles Lost Aerial Challenges Lost Missed Blocked Crosses Missed Tackles Fouls Committed
Defensive Error xG	Where an error results in a shot, the Expected Goals probability resulting from that player’s defensive errors.
Scoring Contribution	The sum of goals and assists for that player.
Expected Scoring Contribution (xSC)	The sum of xG plus xA for that player.
Pack Pass	The total number of passes completed that take out at least one opponent.
Pack Pass Rate	The number of opponents taken out by a completed pack pass.
Pass Impect	The total Impect score for all completed passes by that player, calculated as per Impect Score.
Pack Receive	The total number of passes received that take out at least one opponent.
Pack Receive Rate	The number of opponents taken out by a received pack pass.
Receive Impect	The total Impect score for all received passes by that player, calculated as per Impect Score.
Pack Dribble	The total number of dribbles that take out at least one opponent. The Dribble has to complete with a next action attempted.
Pack Receive Rate	The number of opponents taken out by a Pack Dribble.
Dribble Impect	The total Impect score for all successful dribbles by that player, calculated as per Impect Score.
Total Packs	The total number of Pack Passes, Receives and Dribbles by a player.
Total Pack Rate	The number of opponents taken out by all Packs by that player.
Total Impect	The total Impect score for all successful Packs by that player, calculated as per Impect Score.
Players Per Pack Pass	Average number of players taken out per Pack Pass.
Impect Per Pack Pass	Average Impect score per Pack Pass.
Players Per Pack Receive	Average number of players taken out per Pack Receive
Impect Per Pack Receive	Average Impect Score per Pack Receive.
Players Per Dribble Pack	Average number of players taken out per Pack Dribble
Impect Per Dribble Pack	Average Impect Score per Pack Dribble
Players Per Pack Total	Average number of players taken out per Pack.
Impect Per Pack Total	Average Impect Score per Pack.
Impect Pass %	The percentage of all passes by a player that were Pack Passes therefore generated an Impect Score.
Possession Kept	Sum of all events where possession is maintained for your team or you’ve used possession to have a shot: Completed Passes Completed Set Piece Passes Clearances Shield Outs Fouls Suffered Pack Dribbles All Shots Taken
Possession Lost	Sum of all events where possession is lost for your team: Incomplete Passes Incomplete Set Piece Passes Clearances Miss Controls Cross Fails Offside
Possession Effectiveness Index %	The proportion between Possessions Kept and Possessions Lost.
Usage Rate %	The proportion of Possessions Kept by that player as a % of all Possessions Kept by the whole team.
Open Play Pass Complete %	The proportion of all open play passes attempted that were successful.
Set Piece Pass Complete %	The proportion of set piece passes attempted that were successful. Broken down into Throws, Corners and Free Kicks.
All Pass Completion %	The proportion of all passes attempted that were successful.
Defensive Action Success Rate %	The proportion of Successful Challenges as a % of all challenges attempted (Successful Challenges plus Unsuccessful Challenges)
Shot Accuracy %	The percentage of all shots that were Shots On Target.
On Target Conversion %	The percentage of all Shots on Targets resulting in Goals.
All Shot Conversion %	The percentage of all Shots resulting in Goals.
Chances Created	The total number of Assists and Key Passes.
CAT Score	Celtic Attacking Threat score. The sum of: Shots On Target (Minus Goals) Goals Assists Key Passes Possessions In Box
Minutes Per Scoring Contribution	The average number of minutes played between each assist or goal.
Possessions Per Scoring Contribution	The average number of ball possessions between each assist or goal.
Final Third Effectiveness	A % comparing the number of chances created and shots taken versus the number of final third possessions lost.
Crime Count	Opta call this Disciplinary Points – Opta Event Definitions – Stats Perform
Goalkeeper Saves	Total number of saves by the goalkeeper.
Goalkeeper Conceded	The number of goals conceded by the goalkeeper.

Team Metrics

Team metrics are calculated for both Celtic and the opposition. Note that many metrics are calculated at the team level as well as the Player level as per the Player Metric list above. I am not repeating them.

The list below is the metrics calculated at the Team level but NOT the Player Metric level.

Data Element	Definition
Possession %	The total Possessions Kept and Lost for each team as a proportion.
Shots On Target Ratio %	The percentage of all Shots on Target achieved by each team.
Total Shot Ratio %	The percentage of all Shots achieved by each team.
Corners	Total number of corners won by the team.
Goal Time Segment	The Time portion of the game each goal was scored in. Time segments are: 0-10 minutes 11-20 21-30 31-40 41-45 46-50 51-60 61-70 71-80 81-90 90+
Passes Per Defensive Action	The ratio between the number of attempted passes by one team and the number of defensive actions by the other. It is a measure of pressing. Defensive Actions included are: Tackles Intercepts Fouls
Passes Attempted Per Interception	A measure of how disruptive a teams’ pressing has been. The ratio between the total number of passes attempted by one team and the total number of interceptions from the other.
Passes Attempted Per Tackle	A measure of how disruptive a teams’ pressing has been. The ratio between the total number of passes attempted by one team and the total number of tackles from the other.
Minutes Per Foul	The number of minutes between fouls awarded to each team, on average, adjusted for the possession of each side.
Fouls Per Minutes	The number of fouls conceded in any minute adjusted for possession.
xG Per Shot	The average xG value for each shot attempted.
xA Per Chance	The average xA value for each chance created.

Goalkeeper Metrics

The following are only derived / calculated for Celtic goalkeepers.

Data Element	Definition
xG Saved	The Expected Goals (xG) of the shots saved.
xG Conceded	The Expected Goals (xG) of the goals conceded.

Note also that virtually all Player Metrics are calculated based on:

• a per Game Total;
• a per Season Total; and
• a per 90-minute average.

Where data elements have a success/fail outcome e.g. dribbles, passes, tackles, aerial challenges, there will be a % Successful and % Unsuccessful metric.

I am very happy to have this critiqued and improved upon. I am even more happy to have suggestions for new / better data points and metrics. For example, I do not calculate Expected Goal Chain – the chain of passes leading up to a shot. There is also a school of thought that every pass is an Expected Assist (xA) and should be calculated accordingly.

I should eat, sleep, work and function as a responsible adult so there will be limits to what can be captured by my eye and hand.

Please engage by email or Twitter.