ABSTRACT
There is a preponderance of evidence that feedback is a powerful influence in the development of learning outcomes. Two findings from the many meta-analyses of the effects of feedback are most fascinating-the average effects of feedback are among the highest we know in education, and feedback effects are among the most variable in their influences. From a review of 12 meta-analyses that have included specific information on feedback in classrooms (based on 196 studies and 6972 effect-sizes), the average effectsize was d = .79, which is twice the average effect (Hattie, 2009). This places feedback among the top 10 influences on achievement. The variance of effects, however, was considerable, indicating that some types of feedback are more powerful than others (Kluger & DeNisi, 1996). It appears that merely prescribing lots of feedback does not imply that learning will take place, as one has to take into consideration the differential effects of feedback on learning as well as learners.
