Monday, August 18, 2014

Expected shot values for individual players in the neutral-zone

This post will break down the expected shot values of individual puck-possession plays in the neutral-zone. Here I will use data from every Montreal Canadiens 2013-14 regular season and 2014 playoff game. A list off all the events I track, as well as a breakdown of what that data allows us to calculate can be found here.

Every possession play that occurs on the ice has both an expected goal value (EGV) and an expected shot value (ESV). The expected goal value is represented by the chance of that specific puck-possession play eventually producing a goal. The expected shot value is the chance of that specific play eventually producing a shot on net. Expected goal and shot value can be calculated by using the success-rate of that specific play, as well as the success-rates of all succeeding plays. The goal of this is to determine how successful that play has been to either produce a shot-on-net, or a goal. 
 
The average success-rates for forwards were used for all succeeding plays in each players calculation.


ESV OF AN ATTEMPTED NEUTRAL-ZONE DUMP-IN, FOLLOWED BY A LOOSE-PUCK RECOVERY

A neutral-zone dump in (as expressed in this graph) requires a player to recover a loose-puck in the offensive-zone, successfully pass the puck to a teammate, and have that teammate get a shot through to the net (shot doesn't miss the net or get blocked).

Among attempted neutral-zone puck-possession plays, only chip-ins have a lower expected shot value. The ESV expressed here helps quantify the importance of controlled entries in the production of offense.




ESV OF AN ATTEMPTED NEUTRAL-ZONE CHIP-IN, FOLLOWED BY A LOOSE-PUCK RECOVERY

A neutral-zone dump in (as expressed in this graph) requires a player to recover a loose-puck in the offensive-zone, successfully pass the puck to a teammate, and have that teammate get a shot through to the net (shot doesn't miss the net or get blocked). Once again, the ESV expressed here helps quantify the importance of controlled entries in the production of offense.

Among attempted neutral-zone puck-possession plays, this play has the lowest expected shot value. This is due to a low overall success-rate when attempting to get chip-ins deep into the offensive-zone.





ESV OF AN ATTEMPTED NEUTRAL-ZONE EAST/WEST PASS, FOLLOWED BY A PASS OFF OF THE RUSH

A neutral-zone east/west pass (as expressed in this graph) requires a player to complete a neutral-zone east/west pass, followed by a pass off of the rush, and a shot through to the net.

Players with smaller sample sizes (Beaulieu and Weise) have higher ESV's for this play than other players.




ESV OF AN ATTEMPTED NEUTRAL-ZONE NORTH/WEST PASS, FOLLOWED BY A PASS OFF OF THE RUSH

A neutral-zone north/south pass (as expressed in this graph) requires a player to complete a neutral-zone east/west pass, followed by a pass off of the rush, and a shot through to the net.

Players with smaller sample sizes (Beaulieu and Weise) have higher ESV's for this play than other players.




ESV OF AN ATTEMPTED NEUTRAL-ZONE EAST/WEST PASS, FOLLOWED BY AN O-ZONE DEKE

A neutral-zone east/west pass (as expressed in this graph) requires a player to complete a neutral-zone east/west pass, followed by a successful offensive-zone deke, and a shot through to the net.
 


ESV OF AN ATTEMPTED NEUTRAL-ZONE NORTH/SOUTH PASS, FOLLOWED BY AN O-ZONE DEKE

A neutral-zone north/south pass (as expressed in this graph) requires a player to complete a neutral-zone east/west pass, followed by a successful offensive-zone deke, and a shot through to the net.
 



ESV OF AN ATTEMPTED NEUTRAL-ZONE EAST/WEST PASS, FOLLOWED BY A SHOT

A neutral-zone east/west pass (as expressed in this graph) requires a player to complete a neutral-zone east/west pass, followed by a successful shot through to the net.  Although this has the highest expected shot value among neutral-zone plays, it's expected goal value will depend on the distance of the attempted shot from the net. Next season I will separate shots that are taken while positioned in the slot, from those taken outside of the slot. This will provide more detail to the EGV's produced by my system.





ESV OF AN ATTEMPTED NEUTRAL-ZONE NORTH/SOUTH PASS, FOLLOWED BY A SHOT

A neutral-zone deke (as expressed in this graph) requires a player to beat a player 1on1 (deke) in the neutral-zone, followed by another successful deke in the offensive-zone. 

Not surprisingly, PK Subban has the top ESV in this category. Andrei Markov's positioning in second place was somewhat of a surprise, as number 79 does not attempt to beat players 1on1 with a deke very often. That said, despite the low attempt-total, Markov's success-rate in these metrics are quite impressive.