Abstract:
This paper describes our continuing work on enabling a tutor to evaluate algebraic solutions to word problems in physics. Current tutoring systems require students to explicitly define each variable that is used in the algebraic equations. We have developed a constraint propagation based heuristic algorithm that finds the possible dimensions and physics concepts for each variable. In earlier work we developed techniques that worked for a small set of problems and evaluated them on a small number of students. The work described here covers an extension to and evaluation of a much larger class of problems and a larger number of students. The results show that our technique uniquely determines the dimensions of all the variables in 89% of the sets of equations. By asking the student for dimension information about one variable, an additional 3% of the sets can be determined. Thus a physics tutoring system can use this technique to reason about a student’s answers even when the scaffolding and context are removed.

Published Date: May 2004
Registration: ISBN 978-1-57735-201-3
Copyright: Published by The AAAI Press, Menlo Park, California.