Thanks Fabien for your help! We know have a php script that automatically generates a map of CatchBob! users' path. This map is going to be of interest since I want to calculate the number of error an individual made while drawing his own path like this one (here it is correct). In addition, I will also check if the partners drew this path correctly; on the following drawing, there is a mistake (in red): The main problem here to calculate the number of error is the low accuracy of the positioning tool; I'll just compute a rough error index. Here is the modethodology:

In the post-game questionnaire, we ask players to draw 3 maps: the path they took on the campus plus the map they thought their partner 1 and 2 did. Thanks to the client logs server, we can generate a map of each paths. It allows us to calculate different number of errors that are spatial modelling indexes:

comparison the path player A drawn about where he went to his/her real path. It represents the quality of A’s representation of the physical environment.

comparison between the path player A drawn about B or C to B or C’s paths. It represents the quality of A’s representation of B and C’s behavior in space. For example, on figure 3, we can compare the way A drew his path (in green on figure 2 aboce) to how B drew it (in red on figure 3 above).

Calculating the number of errors is made through the use of layers on printed material. An error is both a place where the player have not been or a place where he went but he forgot to draw it. Three criteria were defined to describe what is an error: distance (if the line is longer than the maximum size of our campus corridor), presence of an obstacle (door/wall/glass), walking back is not perceived as an error.