There will be two lines on the screen: longer and shorter. The shorter line is always movable, ie you can change its length by dragging the mouse in the desired direction.
Your task is to increase the length of the moving line so that it is the same length as the fixed line. To change the length of the scrolling line, click on the scrolling line and drag the mouse in the desired direction (drag and drop). When you have finished scrolling, release the mouse button.
For precize adjustments you can use arrow Up key (increasing) or arrow Down (decreasing line size).
It is not allowed to return to the previous task.
As demo mode is turned on, the ideal solution will be displayed in each task (and error).
Maximize a window (page) before starting the task. You must not resize the screen during the task.
Avoid resizing the page (window) while performing the task. This can have a small effect on all results (decimal rounding errors in the calculation).
Results by items:
Absolute error (px). Descriptive statistics grouped by variable Length and total:
Absolute error = units are pixels (px). Significantly depends on the size (resolution) of the screen used. Absolute error is always positive
Relative error. Descriptive statistics grouped by variable Length and total:
Relative error: units are percentages. The total range is approximately: [-50, 50]. Negative sign: underestimation of the length of the moving line in relation to the length of the fixed line. Positive sign: overestimation of line length. Important: As relative error can be both positive and negative, descriptive statistics for it must be interpreted very carefully.
Inferential statistics - correlations:
To calculate inferential statistics, the line size is converted from user-entered values to pixels.
Note: Ignore or at least very carefully use inferential statistics for small sample size. For an explanation of the terms used, see Options => Latest Research