Some people have strong feelings about non-integer marks. You can allow or disallow their creation by changing these preferences. (Note that this doesn't effect which rubrics can be used).

Create +½, -½, +¼, etc, rubrics based on which fractions are enabled above (make sure you click "Submit" first). Any existing fractional rubrics will be ignored. Hint: if you later want to remove these rubrics, you'll need to “unpublish” them one-at-a-time. {% if not rubrics %}The system rubrics must be created before this button is enabled.{% endif %}

Unpublishing the +δ and -δ rubrics will hide them from markers, effectively disabling their use. This might be desirable if you always want your markers to leave more detailed feedback (although note the ±δ rubrics can be used to give detailed feedback with click-drag highlight rectangles).