Jan 19, 2009

Exclamation Perils of precision

Participants in Amsterdam Real Time [http://www.waag.org/project/realtime] comprised a diverse sampling Amsterdam experiences. A public call for volunteers requested details of each applicant’s occupation, gender, age, travel habits, place of residence, place of work and week-by-week availability. Forms were made available on the Waag’s website and on posters hung throughout the city. Four hundred people responded, motivated as much by curiosity as by a sense of community. Sixty were invited to participate. The only requirement was that for a few weeks during October and November 2002 they had to carry around a slightly bulky pack containing a trace-unit comprising Global Positioning System (GPS) sensors attached to networked personal digital assistants (PDA). Most of the packet could be carried inside a backpack or pocket but in order to maintain a clear line of site with the GPS satellites, the antenna itself had to be worn on the outside of clothing or secured to a car roof.
To form a collective synchronous map referred to “the most current map of Amsterdam”, latitude and longitude coordinates collected by each participant were transmitted to a Waag server via General Packet Radio Service (GPRS). The server compiled the images based on the accumulations of participants’ points over specified periods of time. Frequently traveled points became brighter over time, and the most densely traveled areas, such as Centraal Station, were noted in yellow and then red. Less frequented trails were remained pale gray traces, with physical features such as bodies of water made obvious only by black space lined with dense concentrations of foot traffic over occasional bridge. Every aspect of each image was generated by recent and current activity within the city. The names of participants marked their current locations as they continued to form the map while pursuing their normal daily activities.
Rebecca Ross in Else/Where: Mapping, (pp.185-6)