Education research: college physics midterm statistics

Cuesta College Physics 205A (college physics, algebra-based, mandatory adjunct laboratory) students students take their second midterm in the 15th week of instruction.

The midterm consists of five multiple-choice questions, two short-answer questions, and two worked-out problems, to be completed within 80 minutes (the length of a regularly-scheduled lecture).

Grading statistics:

Cuesta College
Physics 205A fall semester 2011 sections 70854, 70855 
Exam code: midterm02fR3q
Midterm 2 results (N = 53, max score = 75):
 0-15 :   
16-30 : **  [low = 22]
31-45 : ***************
46-60 : ******************  [mean = 52.2 +/- 12.3]
61-75 : ******************  [high = 72]

The order in which students turned in their completed midterms was recorded, beginning approximately 20 minutes after starting, to 80 minutes after starting. With a linear regression r² value of 0.0434, there is no significant correlation between the completion order c turning on the midterm and resulting score S (S = -0.1685c + 56.966).