CONCEPT Cited by 1 source
Estimated Time of Arrival (ETA)¶
Estimated Time of Arrival (ETA) is the predicted clock time at which a trip (vehicle, delivery, transit, courier) will reach its destination, given the origin, the route, live road conditions, and trip-specific features. In consumer mapping products it is the load-bearing number the rest of the UX hangs off — route ranking, turn-by-turn recalibration, sharing "I'll be there at 6:42".
Stub page. The wiki has one ingested source touching ETA so far — Google's HOV-specific ETAs post, which only surfaces the intro. This page will expand substantially as Maps / Uber / DoorDash / logistics ETA posts are ingested; the framing below is a scaffold, not a survey.
Why ETAs are hard¶
- Route-conditioned, not just origin-destination. The same pair of endpoints has many legal routes; each has a different ETA.
- Live traffic is a moving target. Historical priors (time of day, day of week, weather) must be fused with live probe data (vehicles reporting speed / position) under seconds-of-latency freshness requirements.
- Lane type and trip category matter. A single ETA conditioned only on route + time mispredicts when the road network has heterogeneous lanes available to some trips but not others. Google's 2025-06-30 HOV post is the canonical wiki instance of this failure mode: HOV lanes in Utah's Salt Lake Valley averaged 68.18 mph vs. 58.60 mph in general lanes (~16% faster) — large enough that folding HOV and non-HOV traffic into one ETA materially biases both (Source: sources/2025-06-30-google-hov-specific-etas-google-maps).
- Serving latency budget is tight. ETAs are computed inline in the navigation UI and re-computed continuously as the driver moves.
Design moves seen so far¶
- Split ETA surfaces by trip category. Rather than adding category features to a single model and hoping it learns the split, Google Maps HOV ETAs use a dedicated ETA surface conditioned on a trip classifier output (HOV vs. non-HOV). The classifier is the enabling artifact that the specialised surface depends on (Source: sources/2025-06-30-google-hov-specific-etas-google-maps).
- Expose the split in the UI. Route options (e.g., "include carpool lanes") let users opt into the category, so the ETA surface being selected is transparent and controllable.
Seen in¶
- sources/2025-06-30-google-hov-specific-etas-google-maps — HOV-specific ETAs on Google Maps; classification-first design (classify trips → serve per-category ETA surface).