Instructional format and segment length in interactive video programs

The purpose of this study was to gather further insight into a previous investigation of the relationship between self-chosen and program-controlled segment length of an interactive videodisk program, and performance on post- and retention tests. The initial study by Verhagen, which questioned what is the optimum length of well-designed audio-visual segments to present factual information via an interactive video program, is reviewed. The additional research reported here was designed to find out whether the conclusions of Verhagen's study should be altered if data collection is carried out in an instruction experiment rather than a memory experiment. It also studied the effect of the amount of invested mental effort (AIME), and tested achievement of instructional objectives concerning the video program as a whole rather than testing specific information elements. Seventy-three university freshmen were given pre-, post-, and retention tests, and were grouped to learn from the following video segmentation formats: (1) Explore--a menu-driven environment giving subject complete control to choose video segments, segment their length, and jump between knowledge questions and remediation video segments at will; (2) Guide--video sequences are pre-segmented, followed immediately by the appropriate knowledge questions and remediation, and presented in linear order; (3) Linear--instructional objectives are presented beforehand, then subjects watch the entire program without stopping; (4) Variable--subject has control over length of each video segment, but not over sequence of video program. Results show that in a memory performance task, shorter video segments were chosen than those chosen for an instructional task. However, no evidence was found that test performance was related to self-chosen segment length. The Explore and Guide conditions required the least mental effort, and thus provided the most relaxed learning situation and usability. Finally, no relationship between AIME and test performance could be determined. Data is presented in nine tables and figures.