e-Learning and the Science of Instruction: Proven Guidelines for Consumers and Designers of Multimedia Learning

2.5. How Do You Interpret Research Statistics?

Suppose you read a study comparing two groups of students—a test group and a control group. The control group received a basic multimedia lesson that explains content with graphics and audio narration. We call this the no music group. The test group received the same lesson with background music added to the narration. We call this the music group. Suppose the no-music group averaged 90 percent correct on a test of the material and the music group averaged 80 percent on the same test. Averages are also called means (for example, 90 percent versus 80 percent). Also suppose the scores were not very spread out, so most of the no-music students scored close to 90 and most of the music students scored ...