Real-time information changes the wait more than the waiting time

This is written to be used rather than admired. Each section below is a decision about passenger information, and each one has a default.

Uncertainty is the expensive part of waiting

Research on waiting consistently finds that time spent not knowing when a service will arrive is experienced as considerably longer than a known wait. That is why a countdown display can improve satisfaction on a route whose actual performance has not changed at all. It also changes behaviour, since a passenger who knows a long wait is coming can sit down, buy something or take a different route.

Where the information reveals a genuinely poor service, satisfaction can fall instead, which is an argument for fixing the service rather than hiding it. The mechanism is about control rather than about time, and control is what an uncertain wait removes.

Predictions are estimates and behave like it

Arrival predictions are generated from vehicle position and historic running times, so they carry the uncertainty of both inputs. A prediction that increases as the vehicle sits in traffic is functioning correctly, though it reads to a passenger as the system failing.

Over a decade, predictions that jump backwards, or that show a vehicle arriving and then remove it, damage trust disproportionately to their frequency. Systems that present a range rather than a single minute figure are more honest and are less popular in user testing. The design tension is between an honest estimate and a confident one, and most operators have chosen confidence.

Displays and phones reach different people

A phone application reaches people with a suitable device, a data connection, the application installed and the ability to use it. A display at the stop reaches everybody standing there, including occasional users, visitors, and people who will not or cannot use an application. Audible announcements at stops matter for blind passengers and for anyone whose attention is elsewhere, and they are frequently omitted for cost.

In practice, removing physical displays because an application exists is a common saving that transfers cost onto the least connected passengers. The two channels are complements rather than substitutes, and treating them as substitutes is a recurring procurement mistake.

Disruption is where information matters most

Routine information about a service running normally has modest value, since a frequent service does not require much planning. During disruption the passenger needs to know what has happened, how long it will last and what alternative to take, in that order. Most systems are good at the first, poor at the second and almost silent on the third, which is the one that determines the journey.

Alternative routing advice requires the operator to reason about the whole network rather than about the affected line.

Staff on platforms remain the most effective channel during disruption, which is an argument against removing them to fund screens.

Information changes network behaviour

When passengers can see arrivals across modes, they make substitutions between bus, tram and rail that timetables alone would not produce. That flattens loading across parallel services and can improve effective capacity without any new vehicles.

Open data has made this possible in many cities by allowing third parties to build tools an operator would not have built. It also removes the operator from the interface, which some organisations resist because presentation and branding pass out of their control. The evidence generally favours openness, and the operational benefits arrive without the operator having to build anything.

What works in a dense grid may not transfer to a low-density suburb.

What good information looks like at a stop

The display should show the next several departures rather than only the first, since the second one determines whether to wait. It should indicate accessibility, capacity or vehicle type where these vary, because a passenger with a wheelchair needs to know before it arrives.

Measured properly, during disruption it should say what is wrong in plain language rather than showing a blank screen or a cancelled entry. Placement matters, as a display readable only from directly beneath it fails everybody approaching from further along the street. A stop with a clear name, a route diagram and a printed timetable still serves people that no digital system reaches.

The takeaway

Tell people what is happening. It does not speed up the service and it changes the journey.

Cities are built by a thousand small permissions, not one big plan.