Problems and Limitations of Animation
Beyond the problem of split attention mentioned above, psychologist Barbara Tversky and her colleagues have identified four major challenges when people watch and learn from animated graphics (including maps) as compared to the static graphics of the same data:
- Attention: In any visually rich display, especially in an animated map where many things can be happening simultaneously, readers are often unsure of where to look (a problem with the maps) or what to do (a problem with the interface). Potential solutions include guided tours, short tutorials, and voice over.
- Disappearance: By their very nature animated maps change, often quite dramatically from moment to moment. As a result, there is always the potential that the map reader will miss important information or cues. Because of disappearance (i.e., blink and you miss it), many basic map reading tasks can be very
difficult, such as estimating the size of symbols or areas, matching colors to a legend, comparing one symbol to another, or reading text labels.
- Complexity: With (1) the astonishing level of computing and video processing power available today in the basic desktop computer, coupled with (2) the equally astonishing size and complexity of digital databases, it is entirely possible to make an animated map that simply overwhelms readers with data and 'saturates' their visual processing. Data filtering tools and techniques that can help us cope with this complexity have been a major avenue of research in GIScience for 20 years now and many journals and international conferences are devoted to this topic.
- Confidence: Early testing has shown that while people often like looking at animated maps, they are sometimes less confident of the knowledge they acquire from the animation than from static graphics. In response to this blanket concern, others have pointed out that people have far more exposure and experience using static maps, and thus there is naturally a learning curve to animated maps that needs to be understood (and systematically targeted) before we can conclude they do not work. Moreover, there are obviously some representational tasks for which animated maps are poorly suited (and a static map or table are inherently more efficient) and to test animated maps under those conditions is unfair and not especially informative.
It should be noted that none of these challenges are insurmountable and many graphic design solutions have been proposed (and tested) for each of these, primarily relying on increased and/or new forms of interactivity, better interface controls (e.g., more intuitive, less obtrusive), and a willingness to restrain the design of our animated maps so they respect the cognitive and perceptual limitations of the eye–brain system, such as avoiding well understood limitations in human vision such as optical illusions and 'change blindness'. As a way forward, researcher Sara Fabrikant and her colleagues are doing promising work around the notion of 'visual salience' and understanding how people see/understand map animation in order to increase their effectiveness.
Anecdotally, many cartographers will confess they make animated maps because 'they look cool' and, to their credit, the public seems to enjoy watching these maps. Today, animated maps seem to be all around us, from the weather channel, to NASA press releases about lost planetary probes, to nightly television news stories that begin with an animated map that zooms in from space to some foreign locale, thus, connoting an air of (1) currency, (2) powerful panoptical surveillance, and (3) scientific authority to whatever may follow. What is less clear, however, is simply how useful animated maps are when static alternatives are both easier to make and ponder since they do not change. Research that compares the effectiveness of learning from animated and static maps has been mixed and, thus, academic cartographers have an incomplete answer to even the most basic question: 'For what kinds of map reading tasks are animated maps useful, and when should they be avoided?' This does not mean animated maps should be avoided, but rather, like any form of representation, they have their strengths and weaknesses that researchers are working to understand. Animated maps should not be seen as replacements to static maps, but rather as complimentary. They broaden our representational possibilities especially when data have a temporal component.