This valuation is dynamically calculated as a function of the friendship degree that a user has in each moment, and the ratings he/she has received by his/her use of the platform till then. Thus, the system helps users to have an up-to-date reliability measure about whether to trust another user or not. In addition, only users who have a valuation higher than B and/or users who have been accepted by the driver to make the route can see certain driver data, such as the phone number or other specific data. The system threshold for reliability has been set to a value higher than C, that is A or B, because this is the minimum value that represents direct friendship.