Operations Management: An Integrated Approach, 5th Edition

LEARNING CURVES

An important factor in calculating labor times is the learning effect. We all can recall a new task or job that took a long time to finish the first time we tried. However, each subsequent time we did the task, it took less time. This is the basis of learning curve theory. People learn from doing a task and get quicker each time they repeat that task. A learning curve is shown in Figure 11-5.

The major attributes of a learning curve are that it takes less time to complete the task each additional time it is done by the same employee, and the time savings decrease with each additional time that task is done by that employee. When the number of times the task is completed doubles, the decrease in time per task affects the rate of the learning curve. For example, if a learning curve has an 85 percent learning rate, the second time the task is done will take 85 percent of the time it took the first time the task was done. The fourth time the task is done will take 85 percent of the time it took the second time. The eighth time will take 85 percent of the time it took the fourth time, and so on. The formula for calculating the time the task should take is

FIGURE 11-5 Learning curve

T × L_n = time required for nth time the task is done

where T = time needed to complete ...