Encouraging Self-Explanation Through Case-Based
Tutoring: A Case Study

Michael Redmond
Computer Science
Rutgers University
Camden, NJ 08102
(609) 225-6122 Fax: (609) 225-6624
E-mail: redmond@pizza.rutgers.edu

Susan Phillips
Chemistry
Holy Family College
Philadelphia, PA 19114
(215) 637-7700
E-mail: phillips@pizza.rutgers.edu



Abstract. This paper presents a case-based tutor, CECELIA 1.1, that
is based on techniques from CELIA, a computer model of case-based apprenticeship 
learning [Redmond 1992]. The teaching techniques include:
interactive, step by step presentation of case solution steps, student predictions 
of an experts actions, presentation of the experts steps, student
explanations of the experts actions, and presentation of the experts explanation. 
In addition, GECELIA takes advantage of a technique from
VanLehns [1987] SIERRA  presenting examples in an order so that solutions 
only differ by one branch, or disjunct, from previously presented
examples. CEGELIA relies on its teaching strategy encouraging greater
processing of the examples by the student, rather than on embedding
great amounts of intelligence in the tutor. CEGELIA is implemented using 
Hypercard on an Apple Macintosh, and has been pilot tested with
real students. The tests suggest that the approach can be helpful, but
also suggest that eliciting self-explanations from students who normally
do not self-explain may be challenging.
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