Using Decision Scores To Control What Hitters Can Control

Grant me the serenity to accept the things I cannot change, courage to change the things I can, and the wisdom to know the difference.

Hitters we don’t have a lot of control when we step in the box. They can’t control the pitcher, the pitch location, pitch type. Along with the pitcher hitters are subjected to the rule of the umpire. Calling strikes where and when they see fit. Hitters can control over themselves, specifically what pitches they swing at, where the location of the swing is, how often we swing at pitches.

Hitters are consistently frustrated by the strike zones that they get as hitters. Both the inconsistency of different strike locations and the variety of zones that they get on a daily basis. Sometimes it gets to the point where hitters start to question their own understanding of the strike zone. Which can lead them to either consciously or subconsciously start to expand their own strike zone. Players face the decision of choosing between poor results now (expanding the zone to not strike out), and potential growth long term when it comes to their own swing decisions (striking out more often but knowing they made quality decisions).

For a real life example of this situation played out. Here is a batter that had a less than ideal outcome:

TrackMan shows that this pitch is both away, and up when it comes to the strike zone. Clearly a good take. Unfortunately for the batter the pitch was called a strike. As hitters we should be taking this pitch. As the player moves through his career and umpires begin to improve this pitch is one that they should take. The player is sent a signal from the umpire that this pitch was a poor decision. So you can clearly see the dichotomy between results now vs. Development in the future.

How can we help to incentivize players taking this pitch more often? With the help of one our Analyst’s Dan Seguin (Who works really hard, and is good at what he does). Dan developed a Swing Decision Model for us as a team. The goal being that we are able to have a “Decision Score” for each swing that players take in a given game.

After going back and forth about what was best to do either focus on our current level of competition or look to the future with scores coming from MLB Zone. As a staff we came to the conclusion that focusing on the MLB Zone is ultimately the best thing to do. Why prepare players for zones that are less than ideal?

The basic outline of the model is that we wanted to credit and debt players for each of their swing decisions. You score points to good takes, and good swing decisions, you lose points for bad takes, and bad swing decisions. Also baked in to the model for our score is the count at the time of the pitch as well as the overall MLB Swing %. I’m sure Dan can explain this further but this is the most basic understanding of what he built.

Here is a sample plot below:

Left Plot are takes, Right Plot is Swings, from a given Game

Our goal with building this model was to make it so that we can incentivize players to continue to make good swing decisions even though they might face poor outcomes. To make an analogy it is like having a straight flush in poker, only to be beat by a royal flush. Of course this doesn’t feel good but the process behind it should be where we focus.

The goal of the plots is to give players feedback quickly on their own decisions for a given game. Presenting the Take Plot may even be overboard in some situations. So let us narrow down.

Here is a players swing plot with the point values indicated on each point. We can see that the player overall had a negative swing score for the game. We can also see from the plot that really the majority of the negative points came from one really poor swing decision that unfortunately ended the players at bat.

Looked at another way we can see when players start to make good decisions along the way. We can see that this is an example of pitches that were taken that are scored as ‘Good Takes’ but may have had bad outcomes when it comes to the present moment.

These are essentially pitches that most players swing at that are either just off the plate or pitches hitters are not normally barreling up. You can see that each pitch scores big points for the hitter. These types of pitches are typically ones that coaches would expect players to stretch the zone to hit rather than being patient and accepting bad outcomes in certain situations.

Now is this a situation where we present information each and every day, I don’t think that is necessary in every case. I think that Swing Decision Scores should be used similarly to bumpers on the side of a bowling alley. Helping players to steer there way down the lane over time. Making sure that everything is on track so that they can ‘hit’ the pins.

Example of Team Rankings For Decision Scores

By tracking players decisions over the course of a season we can start to see when a player might need to focus in on making decisions or when they should continue to focus on a different area of development.

Really everything that we have made here is simply to help speed up the feedback loop for hitters. Making it so that they understand that the results should be separated from the actual decisions that are being made. It gives them control in a situation where they can’t control much. They leave knowing that even if they have a bad outcome that they followed a sound process. Removing the outcome from the process isn’t easy, but I think that Swing Decision Scores help to make this easier for players to swallow.



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