Elementary Math Models -- Fall 2017

Results for Exam 3

This webpage will give an overview of how the class performed as a whole on the exam.  You can find your individual score posted on Blackboard.  When you get the exam back in class, double check that the score on your paper is the same as what is recorded on blackboard.  Also, add up your points for the entire exam and double check that I have the right total for your paper.  I am very careful totalling and recording scores, but mistakes CAN occur.

Class Performance.  The first histogram below shows all of the scores for the third exam.  The scores are rounded (up) to the nearest whole number, so if you got an 86.5 that would appear as an 87 on the graph.  The graph shows 12 scores of 92, and another 5 in the range from 87 to 89.  So about 60%  of the class scored at 87 or above.    The second histogram shows each student's exam average for the three exams we have completed.  About 3/4 of the students are still on track to earn a B or better in the course at this point. 

However, I am a bit concerned that several students have seen a steady decline in their exam scores.  Part of this may reflect increasing difficulty of the material.  But judging from the results on the exam, it appears that some students who did well at the start of the course were not fully prepared for this exam.  I suspect that some students have not been keeping up with homework, and have been coasting for the last few weeks.  If you are such a student, and if your exam average has fallen below 80,  I strongly urge you to rededicate yourself to doing the assignments.  With a poor showing on the final exam you could end up with an unsatisfactory course grade.

histogram 


Grading Notes.  

Part I Multiple Choice

For each item the instructions said to circle ALL correct statements, and more than one correct statement appears for several of the items.  Accordingly, each statement of each item was scored as if it were a T/F question, with a total of 36 such questions.  I assigned one x for each true statement that was not circled, and for each false statement that was circled.  Your raw score for part I is 36 minus the number of xs.  This was converted to an adjusted score in the range from 0 to 27 by proportional reasoning.  We know that a raw score of 0 should give an adjusted score also equal to 0, and a raw score of 36 should give an adjusted score of 27.  Using proportional reasoning, each point of the raw score corresponds to 3/4 of a point for the adjusted score.  Therefore, the adjusted score equals the raw score times .75.  That result was then rounded up to the nearest half point.  

For example, if you had 5x's, your raw score was 31 and your adjusted score would be (31)(.75) = 23.25. Rounding (up) to the nearest half point gives 23.5.  Your paper indicates the number of xs for each numbered problem, but does not tell you which statements were correct or incorrect.  This is intentional: Your Exam Solutions groups will need to discuss the multiple choice items and come to some consensus about which statements are true, and why.

Part II Problem 3

Each part a through f was scored on a scale of 0 to 10.  This gives a maximum possible raw score of 60.  The raw score was multiplied by 21/60 and then rounded to the nearest half point.  For example, a raw score of 52 would produce an adjusted score of 52(21/60) = 18.2, which is 18 to the nearest half point.  Adjusted scores ending in .25 or .75 were rounded up to the nearest half point.