Uploaded on 2017-02-11 by Heike Kaiser

The photo shows a popular picnic event called "off the grid" that takes place on non-rainy Sundays from April til September. People of all ages and from all over the city travel to a historic neighborhood called "The Presidio" which is a redeveloped former army base, do picnics and are able to purchase food from local or regional food trucks lined up on the edge of a big lawn. One cannot see where the people and the food trucks come from. One can only see some name labels and the fact that the crowd is very heterogeneous. Invisible information that can be derived from this photo and made visible could be: 1. travel patterns of people: where do they come from, where do they go afterwards, which neighborhoods (rich/poor, ethnicities, distance in miles and minutes) 2. origin of the food trucks, both location of company and origin of food (neighborhoods, radius of food supply), 3. weather (number of visitors on warm sunny days in contrast to cooler cloudy days), 4. money spent, etc. Results can be used to establish similar events in other parts of the city to revive neighborhoods and to avoid traffic congestion on Sundays (decentralization).