When reading the
F1.com Bahrain 2023 GP strategy guide I started wondering what is the
margin of error in the race pace estimations
.
Before thinking about error margins however I needed to replicate the estimations reported in the article first. So I downloaded FP1, FP2 and FP3 data from FastF1 and started looking for gaps between RedBull and the rest...
The thing is, I could not really match it.
F1.com as a benchmark
F1.com reports the following gaps to RedBull
Ferarri+0.46s
Mercedes+0.57s
Aston Martin+0.62s
Haas+0.83s
Alfa Romeo+1.05s
Alpine+1.16s
Alpha Tauri+1.21s
Williams+1.35s
McLaren+1.38s
Estimating Race Pace
Assuming Race Pace estimations are based on the long run during FP2, I started looking for 0.46 gap between RedBull and Ferarri. This one I found pretty quickly as a gap between average times of PER and SAI.
But this brings me also to the first question.
What is the definition of the race pace gap estimation?. It seems it should be at least something comparing two runs of the same length, with the same tyre life at the start of the stint. Which means estimating tyre degradation to be able to simulate/extrapolate missing data points. But somehow following this approach I could not get close to the gap reported in the article.
So I went for a
naive approach: Average of lap times of a long stint during FP2. Without taking into account the length of the stint, and the tyre age at the beginning of a stint.
This led directly to the 0.47s gap between RedBull and Ferrari
RedBullPER FP2 SOFT L11-24 97.691s ignoring lap 20 of 102.755s
FerarriSAI FP2 SOFT L19-26 98.148s (+0.47s)
very close to +0.46s
MercedesRUS FP2 SOFT L11-18 98.363s (+0.56s) again close to +0.57s (ignoring lap 23 99.289s)
But further the things started to be tricky. For Aston Martin only ALO did a long run on soft tyre, STR tested on Mediums. And ALO was very fast. Even faster than PER !
Aston MartinALO FP2 SOFT L14-23 97.248 (-0.44s)
Aston MartinSTR FP2 MEDIUM L17-26 98.377 (+0.69s) close to +0.62 reported in the article
So here
it seems that the pace of STR on Mediums is compared to PER and not ALO on Softs. Is it the case? Or is the estimation approach used in the F1.com article different?
The next two estimates following naive approach looks close to the reported ones.
HaasMAG FP2 SOFT L10-14 98.658 (+0.97s) +0.83s from f1.com
Alfa RomeoBOT FP2 SOFT L19-26 98.650 (+0.96s) +1.05s from f1.com
Alpine seems tricky again. Both drivers did long runs on softs. Which one should we look at? And
the gap seems to be much different either way.
AlpineGAS FP2 SOFT L13-22 98.288 (+0.60s) +1.16s on f1.com
AlpineOCO FP2 SOFT L14-23 98.517 (+0.83s) +1.16s on f1.com
The last three teams are again very close to the f1.com estimation following naive approach.
Alpha TauriTSU FP2 SOFT L16-25 98.825 (+1.13s) +1.21s on f1.com
WilliamsSAR FP2 SOFT L17-25 99.022 (+1.33s) +1.35s on f1.com
McLarenPIA FP2 SOFT L13-24 99.004 (+1.35s) +1.38s on f1.com
Bottom Line
There is not enough information in the article to replicate the estimates, and the approach itself is not well defined leaving room for some creativity. But using simple averages gives similar gaps for 8 of 10 teams, indicating this was the way.
Aston Martin and Alpine cannot be matched this way, and I hope someone can point me in the right direction.
Looking forward to hear from you. You can find me on twitter as
@f1scope
And now back to margin of errors...