Maps and Web-based Data - Participatory Mapping: New Data, New Cartography - page 58

Linking various data sources can help keeping the
amount of data to a minimum, thereby rapidly giving
relevance to the application. The LA Bike Map lists the
accidents involving cyclists in Los Angeles using both
contributions by Web users and the city open data. In April
2012, the mapping application had added 149 individual
contributions to the 1,624 reports from the Los Angeles
police station 11 . As claimed by the Alex Thompson, the
association president, adding individual contributions can
help getting a wider picture of the situation:
We mixed the data because we hoped to use the
mix of official and user-reported data to thicken
the data set to where geographic patterns would
be visible. With 6, 000 miles of road, 1, 500
collisions a year doesn't really give a great
picture. Alex Thompson, interview by email, April
17, 2012
Although the use of Web users' contributions to
complement maps can flood the system with unstructured
data 12 , there are archi-texts that can regulate the data-entry
procedure. For instance, they can ask the contributor to enter
all the information needed by the map's moderator in a form.
4.1.3. Dynamic data
The two methods of text circulation explained above (by
adding text or crowdsourcing) require the intervention of the
designers or moderators to transform the data. However,
other data-collection methods can be used to make the text
circulate automatically, such as scraping, through RSS feeds
or APIs. These three types of interchanges among platforms
are also different in terms of access and modification
11 These reports are available to the public 18 months after the events.
12 Not to mention trolling in participatory websites.