What Can Density Charts Teach Us About Players?

Joshua Rodrigues
3 min readDec 11, 2020

When we look at data for players I think often we rush into the information without taking a step back sometimes. I wanted to do that in today’s post and look at what density plots are teaching us about players. Density plots are a common way to display information about specific players. What do these plots look like?

Alright so we can see that we get this mountain type look to the plot. Which is a good analogy to use when we are explaining and teaching these types of plots to coaches and players.

So the question that we are trying to answer when we see plots like this is something like: “How frequently does XYZ event happen?”

For Example we could look into the graphic from above and we can see the following:

So we can start to see the story that this is telling us. That Charlie Blackman has a higher frequency of baseballs that are hit between 80–100 MPH with the most frequent BIP coming at velocities around 90 MPH. (You can see the highest hump in this plot)

Obviously this is a 30000 foot look at Charlie Blackman but you can look into all different areas for hitters start to get a truer look at reality. For example we can start to bring in some Blast Data:

So we can see that this player has a much higher frequency of his Attack Angles happening between 0 and 7ish degrees. With his most frequent Attack Angles happening around 5 degrees.

As with all information this can be manipulated to zoom in or out on a players performance. But understanding the general story that is being told with this type of plot is helpful and should all coaches and players to ask better questions from coaches. Which is what we are looking to do with our players. Do I think that we should end with Density Plot? Probably not but I think that is a really nice way to gather really good information on a player performance.

Want to dig deeper? Here is another article that looks at what I call “Hills” and “Spreads” for these types of plots:

--

--