  Pedestrians often need to decide between different routes they can use to
reach their intended destinations, both during emergencies and in their daily
lives. This route-choice behavior is important in determining traffic
management, evacuation efficiency and building design. Here, we use field
observations and a virtual experiment to study the route choice behavior of
pedestrians around obstacles delimiting exit routes and examine the influence
of three factors, namely the local distance to route starting points and the
pedestrian density and walking speeds along routes. Crucially, both field study
and virtual experiment consider the same scenario which allows us to directly
assess the validity of testing pedestrian behavior in virtual environments. We
find that in both data sets the proportion of people who choose a closer exit
route increases as the difference in distance between exit route starting
points increases. Pedestrians' choices in our data also depend on pedestrian
density along routes, with people preferring less used routes. Our results thus
confirm previously established route choice mechanisms and we can predict over
74% of choices based on these factors. The qualitative agreement in results
between the field study and the virtual experiment suggests that in simple
route-choice scenarios, such as the one we investigate here, virtual
experiments can be a valid experimental technique for studying pedestrian
behavior. We therefore provide much-needed empirical support for the emerging
paradigm of experiments in virtual environments.
