CU-Boulder psychology Professor Gary McClelland had long been frustrated by a lack of illustrations to help him teach statistics classes.
Textbooks provided only limited numbers of pictures because of publishing costs. Overhead projectors and blackboards also had drawbacks.
But advances in technology allowed him to try something new.
"When the Internet and Java came along it struck me that this was the perfect way to provide all the pictures we have been missing in our statistics courses," he said.
The interactive statistics diagrams can be found in McClelland's on-line textbook, "Seeing Statistics," published by Duxbury Press. The first commercially sold, Web-based statistics course combines more than 100 interactive Java applets with real-life examples and discussions of the underlying concepts.
A Java applet is a small program that lets McClelland provide interactive content.
"Each Java applet represents what would have been a thousand photos in a textbook," said McClelland, who spent more than three years developing "Seeing Statistics."
The on-line textbook was tested at more than 150 colleges and universities. It was first used by McClelland's students last fall and will be widely available beginning this month.
Laura Loucks, a CU junior, used the on-line textbook last semester in McClelland's honors class on research methods and statistics.
"It made the material more interesting because it allowed you to manipulate the examples and you weren't limited to what was in a textbook," she said. "And if you got stuck or had a question on one of the problems, it gave you further ways to explore the concepts."
A sample of the interactive applets may be viewed at . The applets illustrate such concepts as the probabilities of rolling certain numbers on dice and how well samples correlate to complete surveys.
"Because statistics is an inherently geometric discipline, it makes a lot more sense to see it in pictures than it does to show equations," he said.
For more information contact McClelland at (303) 492-8617 or Peter Caughey in the Office of News Services at (303) 492-4007.