I believe this can't be done but I'm posting so perhaps it gets on the list of feature changes.
I have a quiz with a formula question that uses a margin of error for the correct answer. Occasionally I find that I've made the margin of error too small (e.g., when they need to use values that are read from a graph which can have a bit of variability). I seem not too always be able to anticipate the appropriate margin of error given the extremes of the variables I use in the question and students' imprecision in reading graphs.
Is there any way to regrade those questions where the margin of error is changed?