EXAMPLE 13.1

Design 1: Does haptic feedback improve performance? In Example 12.1 (page 645), a group of technology students wanted to see if haptic feedback is helpful in navigating a simulated game environment. To do this, they plan to randomly assign 20 students to each of three joystick controller types and record the time it takes to complete a navigation mission.

It turns out that their simulated game has four difficulty levels. Suppose that a second experiment is planned to compare these levels when using the standard joystick. A similar experimental design will be used, with the four difficulty levels randomly assigned equally among the 60 students.