Mappers Blog: Focusing illusion.

fig.1. A post by Rob Plowright under a thread about mapping details in the facebook group Orienteering Mappers Int.

I want to keep this for my records as it can be seen as a nice example of the focusing illusion that contaminates orienteering maps.

It works like this: The mapper constantly overestimates the importance of the feature s/he is just looking at. S/he imagines a course setter or a runner complaining on the generalization of just this feature and thus s/he is horrified of imagined scene. The only viable solution is to map the actual situation in detail, even if in detail makes the map hard to read and to identify the feature itself.

The problem with this approach is obvious. While the course-setter could also be infected by the same focusing illusion the athlete definitely ain't.

The athlete focuses on solving the orienteering task. His/her attention is on matching map with terrain and execution of route choice.

Watch this video. I think this will make my point clear.

As long as the map does not provide wrong information, harming a route choice and thus spoiling a race to the athlete (closed entrance mapped open; impassable fence mapped passable; green worse than mapped) or in other words as long as the gorilla does not block the way, the athlete would never complain about some out-of-bounds stair/bridge generalized. Meanwhile over-mapping due to unconsidered focusing illusion is missing to map in accordance to the maps purpose.