Week 3: The stop — what it costs and what you're allowed

Price a complete pit stop against the laps that would have happened, then find which race strategies survive Friday's tyre returns

8 March 2027

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A stationary service time is not a pit-loss estimate. The clock also runs while the car leaves the track, travels through the pit lane, stops, rejoins, and completes an abnormal in-lap and out-lap. This week we price that whole event against a counterfactual: the same two laps without a stop.

We work one subtraction, then repeat it across Slop University’s synthetic archive. The supplied clean-air laps avoid a second wear fit. Repeated stops turn one worked difference into a mean pit loss with a 95% interval.

The second half starts from the real dry allocation for a Standard Format Competition: 2 hard, 3 medium and 8 soft sets (2026 Formula 1 Sporting Regulations, Issue 08, Article B6.2.4). Friday then removes six sets after the three free-practice sessions (FP1, FP2 and FP3), while named sets for Qualifying — the session that sets the Race grid — and the Race receive protection (Issue 08, Article B6.3.8). Use and return are separate: even an unused set leaves the inventory once it is electronically returned and handed back (Issue 08, Articles B6.4.2–B6.4.3). Alternative Format and ICTT weekends have different allocations and maximum-use figures; ICTT means In-Competition Tyre Testing (Issue 08, Articles B6.1.1, B6.2.4 and B6.3.4).

The deck follows physical set identities through a synthetic SlopU Friday, then enumerates every one- and two-stop compound sequence that the remaining sets can support, including refitting a used set that remains available. The bounded case assumes a dry, uninterrupted race. Under that assumption the car must use two dry specifications, including a mandatory Race specification (Issue 08, Article B6.3.6). A permitted tyre change during a suspension can also count after resumption, so the rule does not say that every dry race forces a conventional stop (Issue 08, Articles B5.14.4 and B6.3.2).

In the lab you produce both outputs: a measured stop cost with uncertainty and the complete legal strategy set for the supplied inventory. Assignment 1’s measurement criterion consumes the first; its model-fitness criterion asks whether the strategy being audited obeys the regulations.