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OLI Economics Example-Tracing Tutors

Tutor Definition: A total of 11 example-tracing tutors developed for the OLI (Open Learning Initiative) project at CMU. These tutors have been integrated with OLI's online Economics course and run over the web. The plan is to implement on the order of 30 additional economics example-tracing tutors so that the entire course is covered.

History: In late 2003 the Economics Example-Tracing Tutors were developed in Java and tested on the OLI site using Java WebStart. In the summer of 2004, the tutors were reimplemented in Flash to improve web delivery.

How the interface was built and how the CTAT tools were used to build the tutor: The original Java versions of the example-tracing tutors were built using NetBeans and Java-based DorminWidgets? as shown on Java Interface Widgets. The Flash version of the example-tracing tutors were developed using an early version of the new Flash-based CTAT tools.

Interface example from the tutor

How interface utilizes scaffolding (make easier for learners by make steps explicit for students instead of implicit) & differ from standard textbook notation: Answers must be provided in cells of a table, in text boxes, or in pull-down menus. The graph provides the correct number of points to be plotted for supply and demand curves.

What distinctive features this tutor has that not all tutors have: The use of a graph as a plotting input device is unique to this tutor. The graph was adapted from a graph applet that was part of the original Economics course.

Scale of delivery: The intent is to use the Economics Example-Tracing Tutors online over many semesters. As of December 2004, the tutors have been used as part of 4 courses.

Publications: The Economics Example-Tracing Tutors are discussed and referenced in the paper: Opening the Door to Non-Programmers: Authoring Intelligent Tutor Behavior by Demonstration; Koedinger, K., Aleven, V., Heffernan, N., McLaren, B. M., and Hockenberry, M. In the Proceedings of the Seventh International Conference on Intelligent Tutoring Systems (ITS-2004), available on our publications page.

For more information about this project, please contact: Bruce McLaren, Senior Systems Scientist, Human-Computer Interaction Institute, Carnegie Mellon University. E-mail: