A passenger information [display] system (PIS or PIDS) is an automated system for supplying users of public transport with information about the nature and state of a public transport service, through visual, voice or other media. Among the information provided by such systems, a distinction can be drawn between:
Static information has traditionally been made available in printed form though route network maps and timetable booklets at transit stations. However most transit operators now also use integrated passenger information systems providing either schedule-based information through a journey planner application or schedule-based information in combination with real-time information.
Real time information is an advance on schedule-only information, which recognises the fact that public transport services do not always operate exactly according to the published timetable. By providing real time information to travellers, they are better able to conduct their journey confidently, including taking any necessary steps in the event of delays. This helps to encourage greater use of public transport, which for many countries is a political goal.
Real-time information is provided to passengers in a number of different ways, including mobile phone applications, platform-level signage, and automated public address systems. It may include both predictions about arrival and departure times, as well as information about the nature and causes of disruptions.
There are four principal considerations for the provision of passenger information (static or real time):
Current operational information on service running is collected from automatic vehicle location (AVL) systems and from control systems, including incident capture systems. This information can be compared algorithmically with the published service timetable to generate a prediction of how services will run in the next few minutes to hours. This may be informed by additional information: for instance, bus services will be affected by congestion on the road network, while all services may be affected by adverse weather conditions.
The capital and revenue costs for traveller information systems can be calculated with reasonable accuracy. However, the derivation of tangible financial benefits is far more difficult to establish and as a consequence, there is very little research. This directs the business model for information systems towards the "softer" merits such as traveller confidence etc. It is worth noting that there must be an actual value as individuals are willing to pay for systems that give them access to real time data relating to their journey. The difficulty is establishing what this is for each individual person and perhaps each individual piece of roadside hardware.