Return Home

Beta Test Discrimination Plots

 

pbc = point biserial correlation: the correlation of an individual problem with the total test.
N = number of test-takers in the sample.

These are plots of the number of people getting a particular problem correct (normalized to N) per total-score bin. The bins are distributed as follows:

 Adjusted Score 
bin size		 Number
 of scores 
-5.75 to  -2 5
-1.75 to   2 17
2.25 to   6 21
6.25 to 10 19
10.25 to 14 33
14.25 to 18 33
18.25 to 22 32
22.25 to 26 66
26.25 to 30 52
30.25 to 34 37
34.25 to 38 25
38.25 to 42 20
Total 360

 

Problem 1

Problem 2

Problem 3

Problem 4

Problem 5

Problem 6

Problem 7

Problem 8

Problem 9

Problem 10

Problem 11

Problem 12

Problem 13

Problem 14

Problem 15

Problem 16

Problem 17

Problem 18

Problem 19

Problem 20

Problem 21

Problem 22

Problem 23

Problem 24

Problem 25

Problem 26

Problem 27

Problem 28

Problem 29

Problem 30

Problem 31

Problem 32

Problem 33

Problem 34

Problem 35

Problem 36

Problem 37

Problem 38

Problem 39

Problem 40

Problem 41

Problem 42

Return Home