Daily Fantasy NASCAR: Introducing the NASCAR Splits App

RotoDoc holds a Ph.D. in mathematics and tackles sports data to give you a competitive edge in your fantasy games.

If you’ve been following my fantasy NASCAR articles you’ll know we’ve been working hard behind the scenes to bring you industry leading NASCAR content. Today we’re excited to unveil the new NASCAR Splits App to add to your arsenal of tools when constructing your daily fantasy NASCAR lineups. You’ll get free use of this app all the way through the Darlington race this Sunday, before it becomes a part of our NASCAR premium package. Here’s the low-down on how to utilize the app to its fullest extent.

NASCAR Splits App

The NASCAR Splits App can be used to answer questions like:

  • How well has Kyle Larson performed at steep tracks in his career?
  • Who has the best average finish over the last 15 restrictor plate races?
  • Who had the highest average running position over the last 12 large oval races where the driver finished the race?
  • Who led the most laps over the last eight races at Darlington?

The app consists of two parts – the inputs and the output. You get to decide what inputs to use. Everything from choosing what years of data to view, to which individual tracks or track groupings, to running status is possible to modify with a few clicks of the mouse. You can even choose how many recent races you want to include and the DraftKings salary range so that you can find the right value plays.

But before we get into the functionality of the app, there will be some terms that need defining and some navigational instructions to go over first.


I’ve grouped the NASCAR venues into similar tracks, mostly borrowed from the work of Cliff  DeJong, but modified by moving Las Vegas from the steep track category into the large oval category. These groupings I’ve given a two letter code as follows:

  • RP – restrictor plate tracks
  • LO – large ovals
  • ST – steep tracks
  • FL – flat tracks
  • RC – road courses

To see which tracks fall in the individual groups, you can simply navigate to the corresponding tabs in the app, circled in red in the screenshot below.


If you forget what each track abbreviation stands for, the results tab has them defined  in the area between the inputs and output table.

Speaking of outputs, the outputs also might have some confusing terminology for those new to NASCAR.

  • AvgFin – simply the average finish as defined by the input choices
  • DRtgdriver rating, which is a nice fun calculated value, but essentially tells you how well the driver performed in a race. This is more predictive than finishing position because a driver could run in first place all race, blow an engine on the last lap, and finish 40th. That 40th place finish wouldn’t be indicative of his performance in that race, or likely future performance.
  • ARP – average running position, which is simply the average position a driver occupied over the course of a race. So if a driver ran half their laps in 12th place, and the other half of their laps in 10th place, his or her ARP would be 11.
  • LLPct – the percentage of laps led
  • FLPct – the percentage of laps that the driver was the fastest driver on track

Like the track type terminology, the output terminology can be found on the results tab between the user defined inputs and the output table.

Using the App

I think the easiest way to show how to use the app is to give a couple examples. In the first example, we want to see how all drivers have performed at all the steep tracks since 2013 (the year NASCAR introduced the newest car style).

Navigate to the app, and the first thing to do is to ensure the year slider is set from 2013-2015. Then, you will want to remove the boxes for “RP”, “LO”, “FL”, and “RC” so that we are left only with the “ST” box in the Track Type filter area. Next, leave the Track Name filter area blank. This automatically defaults to selecting all the tracks contained within the track filter(s) that are selected. In the running status filter, leave both “Running” and “DNF” in, so that we are leaving in every race, even the ones where the drivers had problems. Finally, for the N races filter, you can safely slide it all the way to 36 (there are 6 steep track races per year, with three having been completed so far this year. Thus, going back to 2013 includes 15 races. Setting the slider to 36 ensures you capture all 15 races. Alternatively, you could slide the slider to 15 if you knew before that’s how many steep track races have been completed since 2013). For the salary filter, leave it as is, encompassing the whole salary range. If you got the app to look something like this:


then you did great, and that’s it! To view the results, simply scroll down to the bottom of the results tab and look at the results table. You can sort the results table by any of the output categories, or search for a particular driver in the search box.

Now let’s consider a more complicated example. Let’s figure out how drivers with an upcoming DraftKings salary of $6000 or less have done over the last eight races each driver finished (in other words, no DNF) at the two asphalt surfaced steep tracks, Darlington and Homestead. To do so, we need to set the following sliders:

  • Select Years – 2011-2015 (you can go back farther than 2011 if you want)
  • Track Type – make sure “ST” is included. You can choose to leave the other options in or out, it won’t matter as long as “ST” is there.
  • Track Name – type into the box “Darlington” and “Homestead” and select those two options.
  • Running Status – make sure the “DNF” box is removed, since we only want to look at races where the driver was still running at the end.
  • Select N Races – set the slider to 8.
  • Salary Slider – set the slider range from 5000 to 6000

If your sliders look like this:


you did it right! The output should look similar to the screenshot below.


Let us know what you think of the app, and if you have any suggestions for improvement or ideas for future apps. We’ll be happy to take all the feedback into consideration to give you the best fantasy NASCAR experience possible.

Author Details
Co-Owner and Editor-in-Chief at RotoViz
Co-Owner and Editor-in-Chief at RotoViz. Mathematics Ph.D. 3x qualifier for the DraftKings NASCAR Main Event.
By RotoDoc | @RotoDoc | Archive