Trafikkstatistikk for trikk

The Norwegian Computing Center has been engaged by Ruter AS, the common management company for public transport in Oslo and Akershus, Norway, to develop a method for estimating tram passengers on all trips based on passenger counts on a sample of trips. The method estimates or predicts the number of passengers entering and leaving the tram at every stop, and the number of passengers who stay on the tram between each stop is therefore implicitly estimated as well. All basic predictions are made at stop level on every single trip, and all types of aggregated quantities can therefore be calculated by summing over all single stops of interest, where real data are used when counts are available. Important aggregated quantities include the sum of passengers per year, per month and per day in week, separate for each tram and in total over all lines. Passengergrowth from one year to another can also be calculated. All estimates are given with a quantified uncertainty. The method consists of one model for the number of passengers entering the tram, and another model for passengers leaving the tram. In the latter, the number of passengers leaving the tram is modelled as a proportion of the passengers that stay on the train, which ensures consistency in the predictions. The basic structure of the models takes care of the systematic variation in the passenger data, with multiple seasonality over day, week and year, and typically with similarities between stops. The method is fitted to data from Oslo, but is general in nature, and thus potentially transferable to other regions and similar means of transport.