Statistics 3011 (Geyer, Spring 2006) Grades on Third Midterm

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Contents

Total Scores

   Min. 1st Qu.  Median    Mean 3rd Qu.    Max.
   4.00   48.50   60.00   58.62   71.00   91.00

  0 | 4
  0 |
  1 | 4
  1 | 9
  2 |
  2 | 68
  3 | 0014
  3 | 778
  4 | 14
  4 | 6679
  5 | 1133
  5 | 56788899
  6 | 00000222444
  6 | 57788899
  7 | 1112233
  7 | 7899
  8 | 0044
  8 | 788
  9 | 1

Problem 1

56 of 68 got this right. 4 left it blank.

Problem 2

36 of 68 got this right. 17 left it blank.

Problem 3

57 of 68 got this right. 3 left it blank.

Problem 4

64 of 68 got this right. 0 left it blank.

Problem 5

65 of 68 got this right. 0 left it blank.

Problem 6

54 of 68 got this right. 2 left it blank.

Problem 7

32 of 68 got this right. 12 left it blank.

Problem 8

25 of 68 got this right. 10 left it blank.

Problem 9

  -4 | 0
  -2 | 000000000000000000
  -0 |
   0 | 000000000
   2 | 0
   4 | 00000
   6 | 0000000000000000000000000000000000

Problem 10

  -4 | 000000
  -2 | 0000000000000000000000000000000000000000000000
  -0 |
   0 | 00
   2 |
   4 | 000000000
   6 | 00000

Problem 11

  -4 | 00
  -2 | 0000000000000000000000000
  -0 |
   0 | 0
   2 |
   4 | 000
   6 | 0000000000000000000000000000000000000

Problem 12

  -2 | 00000000000000000
  -0 |
   0 |
   2 |
   4 | 000
   6 | 000000000000000000000000000000000000000000000000

Problem 13

   0 | 00
   1 | 0000
   2 | 00
   3 | 0000
   4 | 0000000000
   5 | 000000000
   6 | 000000
   7 | 0000000000
   8 | 00000000000000000
   9 | 0
  10 | 000

Problem 14

   0 | 00
   1 |
   2 |
   3 |
   4 | 00
   5 |
   6 | 0000
   7 | 000000000000000000000000000
   8 | 0
   9 | 00
  10 | 000000000000000000000000000000

Problem 15

   0 | 000
   1 | 0000
   2 | 00
   3 |
   4 | 000
   5 | 0
   6 | 00
   7 | 0000000000
   8 | 000000
   9 | 00
  10 | 00000000000000000000000000000000000

Problem 16

   0 | 0
   1 |
   2 |
   3 | 000
   4 | 00000
   5 | 000000
   6 | 0000
   7 | 0000000000
   8 | 00000000
   9 | 0000000000000
  10 | 000000000000000000

Problem 17

   0 | 00000000
   1 | 0000
   2 | 00000
   3 | 000
   4 | 0000
   5 | 00000
   6 | 00000000
   7 | 00
   8 | 0000000
   9 | 0
  10 | 000000000000000000000

Problem 18

   0 | 0000
   1 | 0
   2 | 000
   3 | 00
   4 | 0000
   5 | 00000000
   6 | 00000000
   7 | 00000
   8 | 00
   9 | 00000
  10 | 00000000000000000000000000

How to Read the Grades

The grade distributions are shown as stem and leaf plots. For the distribution of the total scores, there is also a six number summary (from the R summary command).

Summary

The summary 

   Min. 1st Qu.  Median    Mean 3rd Qu.    Max.
  46.00   76.00   84.00   82.67   92.00  100.00

shows the lowest score, first quartile, median, mean, third quartile, and highest score.

Stem and Leaf

The distribution follows (produced by the R stem command).

Total Score

For total score, the decimal point is one place to the right of the vertical bar 

   4 | 69
   5 | 0467
   6 | 044778
   7 | 66666668888
   8 | 000222244444444888888
   9 | 02222222222222222222
  10 | 00000000

Hence to the left of the vertical bar are the leading digits of the grades. To the right of the vertical bar are the last digits of the grades. Each single digit on the right represents one grade.

The bottom line says there were 8 perfect scores (100). The next to bottom line says there was one 90 and nineteen 92 scores. And so forth.

Individual Question Scores

For individual questions, the decimal point is at the vertical bar 

  -4 | 0
  -2 | 0000000000
  -0 |
   0 |
   2 |
   4 | 00
   6 | 00000000000000000000000000000000000000000000000000000000000

The bottom line says there were 59 perfect scores (6). The next to bottom line says there were two 4 scores. And so forth.