In July, I saw Iowa State’s Dr. Sarah Nusser give a presentation about spatial ability among survey field representatives and how different people interact with various geospatial technologies. This talk introduced an area of research quite new to me, and it reminded me how important it is to know your audience before designing products for them. It also touched on directly augmenting our sensory perception — more about that below.
When you hire people to collect survey data in the field (verify addresses, conduct interviews, assess land cover type, etc.), you hope they’ll be able to find their way to the sites where you’re sending them. But new hires might come in with various levels of skill or experience, as well as different mental models for maps and geography. Dr. Nusser’s work [here’s a representative article] frames this as “spatial ability” and, practically speaking, treats it as innate: rather than training adults to improve their spatial ability, she focuses on technology and interfaces that help them work better with the mental model they already have. (I can’t believe that spatial ability really is innate and static… but it’s probably cheaper to design a few user-targeted interfaces once than to train new hires indefinitely.)
How do you tell if someone has high or low spatial ability (high SA vs low SA)? One approach is the Paper Folding Test and related tests produced by the Educational Testing Service.
Some examples of differences in spatial ability: High scorers on this test find “north up” maps easier to read, while low scorers prefer maps oriented whichever way the person is currently facing. If your electronic map has a GPS locator and a path tracing where you’ve been, it doesn’t help high-SA people much, but makes a huge difference for low-SA people. Low-SA users are more likely to annotate their map with landmarks they’ve seen on the way, and so on. See Wikipedia on Spatial visualization ability for other examples.
In Nusser’s experiments, volunteer subjects were tested for spatial ability and then asked to go out & verify several addresses. The high-SA people planned their entire route before leaving, then visited them all methodically. But the low-SA people made no plan; after each stop they just tried to find the next-closest address, rather haphazardly. Consequently, low-SA people had much more variable travel times than high-SA people (all the high-SA’s took a similar direct path, while the low-SA’s wandered around randomly)… but if they gave low-SA people a preplanned route and a GPS, the variability in their travel times dropped dramatically. Even though the low-SA folks failed to plan ahead on their own, they admitted afterwards that they wish they’d tried. For a field rep’s manager, it’s great to know that a few minutes spent on planning ahead is a useful investment that will let you budget your reps’ travel times much more accurately.
Some folks favor written step-by-step directions, vs. a map with a route drawn on it, vs. a mental map with landmarks (for locals who know the area already). So, for example, a flexible mapping technology should allow users to minimize the written instructions and widen the map screen, or vice versa. However, if you build your interface around a very powerful/flexible tool, like a full-scale GIS system with zillions of options, you have to make people can actually find the option they need. Nusser tried locking down the flow of the process (“First click here, then click there”) but this was hard for users to remember. They found better results when they just removed functions from the GIS so that only the needed features were there, making it easy for users to find what they need by browsing.
Nusser’s team is testing out other views (bird’s eye view of map, vs. satellite imagery, vs. “egocentric” i.e. like Google Street Maps), showing landmarks better, and finding other ways to work with (not against) the low-SA reps’ cognitive processes. The audience also wondered whether there’s less of a gap between low- and high-SA performance in well-laid-out grid cities than in a jumble-of-paths city like, say, Boston.
Also, Dr. Nusser mentioned one of my favorite bits of trivia: There are languages whose speakers only using cardinal directions, not left and right, i.e. “There’s an ant on your southwest leg” rather than “…on your left leg.” The speakers have an excellent sense of spatial orientation (dead reckoning), wherever they are. There’s a great Radiolab podcast mentioning this phenomenon, around 12 minutes into the episode, at the interview with Dr. Lera Boroditsky. I had no idea that as many as a third of the world’s languages (not speakers) have this feature! New life goal: raise my kids speaking such a language, so they grow up with dead reckoning 🙂
There’s a Wired article describing another approach to dead reckoning: a belt with buzzers that go off to indicate where north is. One of the wearers describes gaining a sudden new perception, like a map in his head — which sounds much like what Dr. Boroditsky discovered after spending time immersed in a dead-reckoning language culture. This belt, by the feelSpace research group at the University of Osnabrück, Germany, strikes me as almost a cyborg enhancement… And in fact Nusser’s group is working on similar lines too: their Project Battuta is developing wearable GIS computing. In both cases, the researchers are building electronic tools to augment our own fragile human abilities.