We have developed different algorithms for measuring the distances traveled, which we constantly improve further. These algorithms validate the stretch data and suggest a probability for a particular locomotive. For example, we have set thresholds for the maximum speed, which should not be exceeded. A distinction between a car and a bus in the city is, however, very difficult. From your mobile phone not clearly definable journeys we collect in "undefined journeys" and enable you with a wipe to define these later.