Tuesday, May 28, 2013

A Simple Way to Measure Raw Speed

(This is a cross-post with BSports StatsInsights)

In this article, I want to come up with a simple way to look at which drivers are the fastest, and to do so in a way that is accessible to a general audience.

What is our metric? It turns out that an effective way to gauge raw speed is to look at the ratio of a driver’s total top 5 finishes to the number of finishes they’ve had on the lead lap.

Why is this a meaningful measure? This ratio tells you, when a driver finishes on the lead lap, what is the probability that they finished in the top 5. A higher ratio implies more pure speed: the driver is faster than the competition and able to convert that speed into results.

This ratio excludes poor performances that result in finishes outside the lead lap, which are races often mired by bad equipment, bad luck, and bad circumstances. Note that because we exclude the worst races, it’s best to consider this ratio as an added dimension to other basic stats. For example, when paired with overall points rank, it's a great way to identify drivers who have a greater potential to outperform their peers. 

Look at Figure 1 below to see who has the best pure speed ratio so far in 2013.




Notice Kyle Busch at the top of the list. After 12 races, he’s had 8 lead lap finishes, and 5 top 5s.  That 5/8 ratio is the 63% you see above.

Denny Hamlin has 3 top-5 finishes in 5 lead-lap-finish races, or a ratio of 60%.

This metric shows how effective Busch and Hamlin have been throughout the season.

Note that this statistic doesn't tell us the complete story. For example, drivers like Paul Menard and Aric Almirola, despite both being in the top 12 in points, are at 0%. 

What does this mean? Menard and Almirola have achieved their rank in the standings not due to pure speed, but rather due to consistency and smart racing.

At this moment, Kurt Busch is 18th in points. But in the pure speed ratio, he ranks 5th overall at 50%, up there with Carl Edwards and Brad Keselowski. This tells us that when Busch has his car setup together, he is doing fantastic. Anybody watching the races this year has known this, but now we have a way to quantify it. Busch is 18th in points not because he lacks speed, but because he lacks consistent finishes. On the flip side, Ricky Stenhouse is 17th in in points because he has finished every race this year, helping to offset his lack of speed, as you see he has a 0% in the pure speed ratio.

What can we do with this new information? And who can use it?
  • Fantasy league participants can find high-potential drivers who can convert their speed into wins. 
  • Team owners looking for young talent can see which drivers have the ability to make it at the next level
  • The media can better identify which drivers are showing pure speed, in a way that filters out distractors such as crashes and bad luck.