MathBrush: A Case Study for Pen-based Interactive Mathematics

George Labahn, Edward Lank, Mirette Marzouk, Andrea Bunt, Scott MacLean, & David Tausky

Summary

Presented in this paper is an evaluation of MathBrush, a pen-math system with tight integration with a computer algebra system (CAS). MathBrush allows users to draw mathematical equations using a pen. Then, using sketch recognition the system attempts to recognize what the user has drawn and convert that to a computer-rendered and -processable representation. A contextual interactive editing affordance allows users to correct errors in recognition. A pop-up menu allows them to execute commands on the recognized expressions.

The evaluation consisted of thinkalouds and semi-structured interviews. Participants were asked to enter and manipulate several mathematical equations using MathBrush. The study showed that participants had no problems entering equations. Several issues arose from recognition, including problems with participants leaving erraneous ink. Participants were able to correct recognition problems, but not without some difficulty related to having multiple representations of the same equation. The contextual pop-up menu allowed participants to easily access mathematical commands, and proved to be one of the stronger aspects of the system. The authors noted that participants adjusted their drawing style to deal with recognition issues.

Discussion

The authors conducted a case study of a pen-math system called MathBrush, and found that participants were able to "effectively" use the system with a few problems with recognition and interaction. The pop-up menu and CAS portion of the system seemed to function the best.

I am not convinced that the participants were able to "effectively" use the system. The difficulties in recognition of sketches and understanding the affordances for correction and editing seem to hinder "effective" use. No qualitative results were presented about the participants' experiences using MathBrush. I think that is one missing piece in this qualitative evaluation.

The user's adapation to the systems shortcomings is an interesting research topic. I would be curious how easily users are able to adapt and what effects it has on cognition. I would research this further.