An attempt was made to determine the effects of different types of instruction on task accomplishment. Three groups of 19 subjects each were given a nonsense wiring task on an IBM machine control panel under three conditions of instruction: diagrammed instruction, diagrammed instructions with additional references on the control panel, and written instructions with the additional references on the control panel. It was found that the group using the diagrammed instructions with the additional references on the control panel had longer task accomplishment times than the other two groups. There were no significant differences among the three groups in errors committed.
