This question is about Feedback/Knowledge of Results in Motor Learning and Control

Information about my lab: In this lab you'll investigate the effects of the precision of Knowledge of Results (KR) feedback on motor performance. The task involves estimating a five second time interval without the use of an external timing device. After each trial, you'll receive feedback that will increase in precision as you go through the different blocks of trials, beginning with trials in which you'll receive no feedback, followed by qualitative feedback ("too short"/"too long"), followed by 3 levels of quantitative KR: 1) +/- 1 second, 2) +/- 0.1 second, and 3) +/- 0.01 second feedback. After completing these trials you'll also perform a transfer task by estimating the time of a 10 second interval. At the end of the lab, you'll be provided with mean Absolute Error (AE) scores for each condition in a data file that you can save to your computer. Record the mean data from each of the feedback conditions into the accompanying Excel spreadsheet for further analysis.

My question: Why was the mean absolute error (AE) used as the outcome variable instead of constant error (CE)?

Feedback Condition No KR Qualitative KR 1 1 sec. KR 1 0.1 sec. KR 1 0.01 sec. KR Transfer task (10 sec.) Mean AE 0.737 0.363 0.212 0.427 0.35 1.365 1.6 1.4 1.2 1 Mean AE 0.8 016 0.4 0.2 No KR Qualitative KR # 1 sec. KR 0.1 sec. KR + 0.01 sec. KR Transfer task (10 sec.) Feedback Condition