Your task is to use the Drag and drop action to move a small vertical line to the middle (half) of the line so that it is equidistant from both ends of the line.

As this is a demonstration task, a small vertical line is placed in the optimal position, i.e. in the middle of the line. You can turn this off in the options.

When you are done, click the button at the bottom right of the screen to display the next task.

To return to the previous task, click the button at the bottom left of the screen.

Results by items:

Descriptive statistics

The error percentage is shown in red. The minimum possible error is 0% of the line length. The maximum possible error is 50% of the line length (total range: 0-50)