Scott MacLean

PhD Graduate, University of Waterloo
Office:DC 2302D
Phone:+1 519 888 4567 x35435
Mail Address:Scott MacLean
David R. Cheriton School of Computer Science
University of Waterloo
200 University Ave. W.
Waterloo, ON, Canada N2L 3G1

Welcome to my website! As of April 2014, I have finished my PhD studies! Previously, I was a doctoral student in the Symbolic Computation Group at the University of Waterloo. My supervisor was George Labahn.

My current resume is available here.


I was a member of the MathBrush project from roughly 2003-2014. This project focused on the development of computer and tablet applications allowing intuitive input and manipulation of hand-drawn mathematics.

I wrote the symbol recognition component of our prototype application, MathBrush, as a co-op student. As a Master's student, I began overhauling the math recognition system and developed new techniques for generating ground-truthed transcription corpora. (The corpus resulting from this research is available from As a PhD student, I continued to work on the recognition system.

When I completed my studies in 2014, the MathBrush recognizer had placed second in an international recognition contest behind a corporate entrant. Our recognizer is based on relational grammars and parse forests, which simultaneously capture a multitude of interpretations of the user's input. The construction of the parse forest is influenced by three low level classification systems responsible for grouping strokes into potential symbols, recognizing those potential symbols, and identifying spatial relationships between symbols and subexpressions. Individual trees are then extracted from the parse forest and reported to the user in decreasing score order. We have experimented with several scoring methods based on both fuzzy sets and probability theory, and currently use a Bayesian model.



Refereed publications

Unrefereed publications

Other talks

Posters presented at local meetings

Last modified in September, 2014.