Email: | smaclean@cs.uwaterloo.ca |

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! I am a doctoral student in the Symbolic Computation Group at the University of Waterloo. My supervisor is George Labahn.

I am a member of the MathBrush project, which researches approaches to building applications allowing intuitive input and manipulation of hand-drawn mathematics on PC tablets. I wrote the symbol recognition component of our prototype application, MathBrush, as a co-op student.

My Master's thesis work was a preliminary investigation into a new approach to semantic analysis, the phase of recognition that attaches semantic meaning to symbol arrangements. In particular, I investigated the view that mathematical handwriting is structured but uncertain, in the sense that we know it possesses a certain amount of structure, but it is not clear what all the small pieces are and how they fit together. I developed a preliminary parser that used fuzzy set theory to model recognition uncertainty and relational context-free grammars to model the formal structure of two-dimensional math syntax. The formal model captures all valid semantic interpretations of a users' writing, while the fuzzy sets allow for differing confidence for each interpretation.

Another aspect of my Master's work, which I wrote my thesis on, deals with issues related to recognition accuracy and sketch corpus creation. I analysed the requirements and practicalities of corpus creation, and offered a standard methodology to follow when creating ground-truthed corpora so that they may be maximally useful for training and evaluating recognition systems.

My doctoral research expands on the themes touched on in my Master's work. I am currently working on the following problems:

- applying Bayesian analysis to the multi-dimensional parsing problem
- improving the complexity of multi-dimensional parsing
- find other efficient and effective ways to intelligently resolve recognition ambiguities
- attempt to systematize the combination of formal descriptions and ambiguity models
- work to standardize measurement schemes for recogizer accuracy and establish recognition contests

- S. MacLean and G. Labahn.
*A New approach for recognizing handwritten mathematics using relational grammars and fuzzy sets.*International Journal of Document Analysis and Recognition, Vol. 16, 2013. pp. 139-163. - S. MacLean, D. Tausky, G. Labahn, E. Lank, and M. Marzouk.
*Is the iPad useful for sketch input? A comparison with the Tablet PC.*Sketch-based Interfaces and Modeling, 2011, pp. 7-14. Online appendix. - S. MacLean, G. Labahn, E. Lank, M. Marzouk, and D. Tausky.
*Grammar-based techniques for creating ground-truthed sketch corpora.*International Journal of Document Analysis and Recognition, Vol. 14, 2011. pp. 65-74. - S. MacLean, D. Tausky, G. Labahn, E. Lank, and M. Marzouk.
*Tools for the efficient generation of hand-drawn corpora based on context-free grammars.*Sketch-based Interfaces and Modeling, Seventh Symposium on, 2009. pp. 125-132. - G. Labahn, E. Lank, S. MacLean, M. Marzouk, and D. Tausky.
*MathBrush: A system for doing math on pen-based devices.*Document Analysis Systems, Eighth IAPR Workshop on, 2008. pp. 599-606. - G. Labahn, E. Lank, M. Marzouk, A. Bunt, S. MacLean, and D.
Tausky.
*MathBrush: A case study for pen-based interactive mathematics.*Sketch-based Interfaces and Modeling, Sixth Workshop on, 2008. pp. 142-150. - G. Labahn, S. MacLean, M. Marzouk, I. Rutherford, and D. Tausky.
*A Preliminary report on the MathBrush pen-math system.*Maple 2006 Conference, 2006. pp 162-178.

- S. MacLean and G. Labahn.
*Margin trees: a data structure for relationship classification in handwritten mathematical expressions.*November 2013 Preprint. - S. MacLean, G. Labahn.
*Recognizing handwritten mathematics via fuzzy parsing.*University of Waterloo Computer Science Technical Report CS-2010-13, 2010. - S. MacLean, G. Labahn, E. Lank, M. Marzouk, D. Tausky.
*Toward math-literate computers.*GRAND National Conference, 2010. (See also the associated poster.) - S. MacLean and G. Labahn.
*Elastic matching in linear time and constant space.*Document Analysis Systems, Ninth IAPR Workshop on, 2010 (short paper). - S. MacLean.
*Techniques for creating ground-truthed sketch corpora.*MMath thesis, University of Waterloo, 2009. - S. MacLean.
*Matching techniques for mathematical symbol recognition.*Internal report, Symbolic Computation Group, University of Waterloo, 2007. - S. MacLean, G. Labahn.
*Segmenting handwritten mathematical expressions.*Maple 2006 Conference, 2006. - G. Labahn, S. MacLean, M. Marzouk, I. Rutherford, and D. Tausky.
*MathBrush: An experimental pen-based math system.*Dagstuhl Seminar Proceedings.

- S. MacLean.
*Tools for hand-drawn corpus generation.*Pen-based Mathematical Computation, Third International Workshop on, 2009. - S. MacLean, G. Labahn.
*Mathematical symbol recognition in the MathBrush system.*CMS-MITACS Joint Conference, 2007.

- S. MacLean.
*Comparing and combining ORCCA symbol recognizers.*ORCCA Joint Lab Meeting (Dec. 2010). - S. MacLean.
*Elastic matching in linear time and constant space.*ORCCA Joint Lab Meeting (Jan. 2009). - S. MacLean.
*Fuzzy parsing and fuzzy branchings.*ORCCA Joint Lab Meeting (Dec. 2008). - S. MacLean.
*A parsing algorithm for a class of relational context-free grammars.*ORCCA Joint Lab Meeting (March 2008). - S. MacLean, G. Labahn.
*Comparing Isolated Symbol Recognition Methods.*ORCCA Joint Lab Meeting (2006).

*Last modified in November, 2013.*