PSYC 1000, Exam 1, February, 2008

    To determine your current standing in the class, you should take your exam score (posted in BlackBoard) and add  five points if you have completed one unit of research participation.  If you have completed two units of research participation (one required, one for extra credit), add ten points to your score in BlackBoard.   If that yields 90 or more, you have an A, 80 or more a B, 70 or more a C, 60 or more a D, below 60 an F.

    Here are some statistics on distribution of grades.  In computing these statistics I have assumed that every student has earned one research participation credit (worth five points).

Grade


Frequency Percent Valid Percent
Valid A 16 17.6 18.0
B 22 24.2 24.7
C 19 20.9 21.3
D 16 17.6 18.0
F 16 17.6 18.0
Total 89 97.8 100.0
Missing Inc 2 2.2
Total 91 100.0
 
Bar Chart


Median 76.00
Std. Deviation 21.678
Skewness -1.606
Minimum 5
Maximum 100

    Quick Summary
  • Half the students got a 76 or better.
  • The scores ranged from 5 to 100.
  • A few very low scores resulted in the distribution having great negative skewness.
  • The most frequent grade was a B.

Does Taking the Practice Tests Help?

BlackBoard keeps track of who has and who has not taken the practice tests that I made available to you online. I do not use this information for grading purposes, but I was curious about whether or not taking those practice tests was associated with performance on the exam. Here are some analyses that address that question.
Chapter 1 Practice Test

Chapter1 N MeanStd. Deviation
Exam_1 0= did not take 43 64.8424.738
1= did take 46 78.2816.079

Independent Samples Test


Levene's Test for Equality of Variances t-test for Equality of Means
t df Sig. (2-tailed)Mean Difference
Exam_1 Equal variances not assumed -3.018 71.338 .004-13.445

On average, those who took the Chapter 1 practice test scored 13.4 points higher than those who did not.  This difference is statistically significant.  A little more than half of the students took this practice test.
 
Chapter 2 Practice Test

Chapter2 N MeanStd. Deviation
Exam_1 0= did not take70 68.84 22.897
1= did take19 82.6311.393

Independent Samples Test


Levene's Test for Equality of Variances t-test for Equality of Means
t df Sig. (2-tailed)Mean Difference
Exam_1 Equal variances not assumed -3.644 60.221 .001-13.789

On average, those who took the Chapter 2 practice test scored 13.8 points higher than those who did not.  This difference is statistically significant.  Only 19 of 89 students took this practice test.

Chapter 3 Practice Test

Chapter3 N MeanStd. Deviation
Exam_1 0= did not take76 69.36 22.234
1= did take13 86.0010.000

Independent Samples Test


Levene's Test for Equality of Variances t-test for Equality of Means
t df Sig. (2-tailed)Mean Difference
Exam_1 Equal variances not assumed -4.418 36.679 .000-16.645

On average, those who took the Chapter 3 practice test scored 16.6 points higher than those who did not.  This difference is statistically significant.  Only 13 of 89 students took this practice test.