by Matt Blair
The emergence of free and (relatively) easy to use mapping tools has created an explosion of mapping activity, and the results vary widely in terms of usability.
As part of our research, we have been trying to identify some of the attributes that make maps effective.
Here is a preview of some of our suggested practices:
- Decide what questions you want the map to answer before you start. Review frequently as you collect data and build your map.
- Answer one question per map. If you are generating KML, you can always combine data files and features later.
- Coordinates are just metadata. Don’t forget the data! Be sure to address questions like: What happened? Is this different from the norm? Why is it important? What should we do about it?
In addition to coordinates, critical metadata for a placemark includes:
- sensitivity and security
- source
- accuracy
- description
- reported and “valid until” timestamps
- contact information and/or links to original or additional data
Crowd-sourced data is often incomplete. Simply adding these last two metadata elements could make a huge difference. Any connection of data back to the real world can make inert data actionable.
To expand on that last point, a placemark on a map after a hurricane that is labelled “Shelter”, with a balloon that says “Capacity: 200 beds” is of limited use. Do they still have 200 beds? How many people are there now? Are they up and running? Do they have power, water and supplies? Have they shut down already?
When there just isn’t time for detailed data collection, the most critical information to include is the contact information: who can I call or text or email to find out the current status?
Stay tuned for additional suggestions on how to make your maps effective.
Update (10/14): I’ve expanded on these ideas in section five of our recent webinar. Slide are available here (PDF, 15.8 mb) with video to follow.
