Home Site

    Page 51
16.4 Table of Contents Bottom of Page Site Map
the Boston area developed it. At the time, I was Professor of Business Data Processing at Miami-Dade Community College. While running the 1st Class Fusion demo programs I realized that the expert system shell was similar to a computerized multiple-choice test. I quickly acquired a Fusion developer's license, and started computerizing the multiple-choice tests I had developed over the years. I was the first professor, in a very large five-campus college, to computerize all of my exams. For this achievement, I won a League of Innovation award. Actually, this was a cheap trick since I employed expert system shell technology to quickly computerize my multiple-choice tests and not for its technical excellence.

Illustration of Simple Multiple Choice Exam

For the purpose of illustration, here is a simple three-
question test expressed in a modern knowledge based system: Knowledge Builder from Attar Software. It expresses the logic for the test's execution flow as a graphical decision tree. One creates tests by drawing decision trees and maintains these tests by editing these trees. Today, anyone with basic computer literacy skills can draw and edit these decision trees. An "inference engine", the run-time component of the knowledge based system, traverses these trees displaying dialogs, performing calculations, and keeping records in the background as well as generating reports.
This system starts with a Login procedure, which
initializes the test and sets up record keeping. The system then displays a dialog for question 1 (Q1 in Figure 1), a multiple-choice question, which may be in any form: a windows dialog,
an HTML page, etc. After collecting the input (a, b, c or d) from this dialog, the test system moves forward through the tree. If 'a' was the answer to Q1, then the system runs the Score procedure, move through Label_1 and onto Q2. If the student answers with 'b', 'c', or 'd', the system moves through Label_1 on to Q2, skipping the Score procedure. The system progresses through the tree arriving at the Report node, where the system completes additional record keeping and reporting.

Discovering Assessment Driven Adaptive Tutorial Systems
I soon realized that creating multiple-choice tests with
an expert system shell ignored most of the shells important features and advantages. For example, in a simple, linear, computerized, multiple-choice test, you move from question 1 to question 2, etc., until you reach the last question. However, by using an expert system shell, the answer to the first question can determine the selection of the second, and how you answer the second question can determine the selection of the third and so on. Finally, you reach one of many conclusions - a result of how you answered the questions presented to you. In most cases, you reach a conclusion without seeing all of the questions. This is very efficient, but how does it improve testing?
This suggests that you must design multiple-choice
questions differently. Previously, you had a question stem, a correct answer and a set of wrong answers (distracters). You were only interested in whether the student answered the question correctly or incorrectly. This produced a score, which when combined with scores from other questions, were

To Page 50

16.4 Table of Contents
Top of Page

To Page 52

16.4 2002

PC AI Magazine - PO Box 30130 Phoenix, AZ 85046 - Voice: 602.971.1869 Fax: 602.971.2321
e-mail: info@pcai.com - Comments? webmaster@pcai.com