The Effect of Decreasing Response Options on Students' Evaluation of Instruction
This study examined the statistical effect of changing from a 10-point to a 5-point response scale on students' evaluation of instruction. Participants were 5,616 students enrolled in classes offered by the College of Social Sciences and Public Affairs at a large Western university, who completed both the old evaluation (10-point response) and the new evaluation (5-point response). On average, students used a greater range of points on the scale for the 5-point scale (32 percent) than on the 10-point scale (19 percent). The effects of changing the response scale are discussed.
Landrum, R. Eric and Braitman, Keli A.. (2008). "The Effect of Decreasing Response Options on Students' Evaluation of Instruction". College Teaching, 56(4), 215 - 218. http://dx.doi.org/10.3200/CTCH.56.4.215-218