Feedback on Numeric Precision - mkraska/meclib GitHub Wiki

Note: This is included in fb_unit.

Provides feedback on how many percent an answer is off from the reference. Even though this gives a strong hint on the correct answer, students tend to not use proportions in order to compute the correct result in the next try.

Note the handling of negative teacher's answers. The difference between student's answer and teacher's answer is normalized by the absolute value of teacher's answer, not by it's signed value.

  • tans: -10, sans: -20, off by (-20+10)/abs(-10)= -100%

This is consistent with deviation by negative % value meaning that the value is too small (to the left of the correct value on the number line).

PRT

Feedback Variables

dev: (sans-tans)/abs(tans)*100;

Any PRT Node

Typically the "false" branch of the first test.

Your result is off by {@dispdp(dev,1)@}%.