A computer-implemented method of evaluating an attribute of a plurality of points of interest, comprising: obtaining position data comprising a plurality of traces (154,156,158) representative of the variation in position of a plurality of devices (4a-4e) over time, each device being associated with a user; associating a region with a point of interest, the point of interest having an assigned category based on the nature of the goods and/or services offered at the point of interest; determining a proportion of the number of users entering the region associated with the point of interest in a time period to a total number of users for whom position data has been obtained from a comparison of the obtained position data with position data defining the associated region; determining a speed of each user within the region associated with the point of interest in the time period and/or the length of time each user spends within the region associated with the point of interest in the time period; associating a region with a further point of interest, the further point of interest having the same assigned category as the point of interest; determining a proportion of the number of users entering the region associated with the further point of interest in the time period to a total number of users for whom position data has been obtained from a comparison of the obtained position data with position data defining the associated region; determining a speed of each user within the region associated with the further point of interest in the time period and/or the length of time each user spends within the region associated with the further point of interest in the time period; evaluating, for the point of interest and the further point of interest, a quality parameter according to the determined proportion of the number of users entering the associated region in the time period and at least one of the speed of each user within the associated region in the time period and the length of time each user spends within the associated region in the time period; determining a rank for the point of interest and the further point of interest according to the quality parameter for each point of interest; and storing and/or transmitting the determined rank for subsequent display to a user. obtaining position data comprising a plurality of traces (154,156,158) representative of the variation in position of a plurality of devices (4a-4e) over time, each device being associated with a user; associating a region with a point of interest, the point of interest having an assigned category based on the nature of the goods and/or services offered at the point of interest; determining a proportion of the number of users entering the region associated with the point of interest in a time period to a total number of users for whom position data has been obtained from a comparison of the obtained position data with position data defining the associated region; determining a speed of each user within the region associated with the point of interest in the time period and/or the length of time each user spends within the region associated with the point of interest in the time period; associating a region with a further point of interest, the further point of interest having the same assigned category as the point of interest; determining a proportion of the number of users entering the region associated with the further point of interest in the time period to a total number of users for whom position data has been obtained from a comparison of the obtained position data with position data defining the associated region; determining a speed of each user within the region associated with the further point of interest in the time period and/or the length of time each user spends within the region associated with the further point of interest in the time period; evaluating, for the point of interest and the further point of interest, a quality parameter according to the determined proportion of the number of users entering the associated region in the time period and at least one of the speed of each user within the associated region in the time period and the length of time each user spends within the associated region in the time period; determining a rank for the point of interest and the further point of interest according to the quality parameter for each point of interest; and storing and/or transmitting the determined rank for subsequent display to a user.