Performance Errors Are Not Systematic

The degree to which your performance in one task is predictive of how you'll do on other tasks. If a child is showing conservation in this task, that's predictive that they'll fail to show conservation elsewhere. So if my speech is broken because I'm rushing, right, it's not going to be broken when I'm not rushing. And as the circumstances change, the patterns of error will change and go all over the place. These errors are not systematic in nature.