int_constructor_car_fe_isolation

Driver-isolation car term: a thin reader over data/fits/constructor_car_fe_isolation.parquet, fitted by fit_constructor_car_fe.py —panel isolation (mean y_s ~ 1 | driver_id + constructor_race on driver-race means of the pre-cliff Ω laps, separately in each era; fit_method constructor_car_fe_isolation_hdfe_v2), re-centred to a lap-weighted mean of zero inside each race.

Part of the Skill family.

Driver-isolation car term: a thin reader over data/fits/constructor_car_fe_isolation.parquet, fitted by fit_constructor_car_fe.py —panel isolation (mean y_s ~ 1 | driver_id + constructor_race on driver-race means of the pre-cliff Ω laps, separately in each era; fit_method constructor_car_fe_isolation_hdfe_v2), re-centred to a lap-weighted mean of zero inside each race. Fitted on the same scale as y_s, unlike int_constructor_car_fe (pace_delta_s, before compound and dirty air come out), so subtracting it does not take strategy and traffic out twice. There is no global-driver fallback: a team whose drivers drove for no other team in the era is an island (‘unidentified’, NULL), and a cell with only one of the team’s drivers in the fit is ‘not_estimated’ (NULL). Negative = faster. Leakage: a function of the residual trajectory; no ML-contract mart may depend on it (T48, ml/tests/test_manifest_contract.py). WI-16a, _roadmap/_fixes/wi/WI-16-cumulative-driver-isolation.md.

Lineage

Overview

Property	Value
Layer	intermediate
Family	Skill
Contract enforced	No
Tags	driver_isolation, constructor

9 tests guard this model - 9 generic, 0 singular.

Columns

Column	Type	Nullable	Tests	Description
constructor_car_fe_isolation_id		Yes	not_null, unique	Surrogate PK = race_year_raceid_constructorid.
race_year		Yes	not_null	Season.
race_id		Yes	not_null	FastF1 event id, e.g. 2021_8.
constructor_id		Yes	not_null	Constructor (stg_laps.constructor_id).
era		Yes	not_null	Regulation era: pre<era_boundary> or post<era_boundary> (var era_boundary, 2022).
n_laps		Yes	not_null	Ω laps of this constructor in the race: the re-centring weight.
car_fe_raw_s		Yes		The fitted constructor×race FE before re-centring, s on the y_s scale; NULL when not identified.
car_iso_s		Yes		Isolation car term, s, NEGATIVE = FASTER than the race’s lap-weighted car (int_constructor_car_fe_isolation). NULL when not identified.
car_term_source		Yes	not_null, accepted_values	Where car_iso_s came from: driver_id (fitted per-era), unidentified (multiple components in race), not_estimated (pyfixest singleton), or no_fit_row (no row in the fit).
race_components_n		Yes		Connected components the race’s constructor×race cells span under the driver key used; 1 = every car level in the race is comparable.
connectivity_note		Yes		The fit’s per-era connected-set diagnostics and fallback decision.
fit_method		Yes		Provenance fit identifier (constructor_car_fe_isolation_hdfe_v1).
fit_timestamp		Yes		Provenance UTC timestamp of the fit.