Item Characteristic Curve and Item Information Function: Item9

skill_level: 5 p: 0.99 skill_level: 4 p: 0.984 skill_level: 3 p: 0.958 skill_level: 2 p: 0.893 skill_level: 1 p: 0.754 skill_level: 0 p: 0.53 skill_level: -1 p: 0.293 skill_level: 0 iif: 0.249 skill_level: -1 iif: 0.207 skill_level: 1 iif: 0.185 skill_level: -2 p: 0.132 skill_level: -2 iif: 0.115 skill_level: 2 iif: 0.0957 skill_level: -3 iif: 0.0503 skill_level: -3 p: 0.0532 skill_level: -3 p: 0.0532 skill_level: -3 p: 0.0532 skill_level: -3 p: 0.0532 skill_level: 3 iif: 0.0405 skill_level: -4 iif: 0.0198 skill_level: -4 p: 0.0202 skill_level: 4 iif: 0.0157 skill_level: 5 iif: 0.00590523239435 skill_level: -5 iif: 0.00748288696116 skill_level: -5 p: 0.00753973455837 skill_level: -5 p: 0.00753973455837
Plot of iif * skill_level


Distracter analysis table: Item9

The FREQ Procedure

Frequency
Col Pct
Table of A9 by Skill_level
A9(A9) Skill_level Total
-2 -1 0 1 2 3 4
A 4
40.00		 39
30.23		 112
21.21		 98
10.82		 18
2.08		 4
0.88		 1
0.42		 276
 
B 1
10.00		 33
25.58		 76
14.39		 42
4.64		 14
1.62		 0
0.00		 0
0.00		 166
 
C 2
20.00		 32
24.81		 108
20.45		 62
6.84		 25
2.89		 3
0.66		 2
0.83		 234
 
D 3
30.00		 25
19.38		 232
43.94		 704
77.70		 808
93.41		 450
98.47		 237
98.75		 2459
 
Total 10 129 528 906 865 457 240 3135
Frequency Missing = 37


Distractor analysis plot: Item9

Skill_level: 4 prob: 0.988 A9: D Skill_level: 3 prob: 0.985 A9: D Skill_level: 2 prob: 0.934 A9: D Skill_level: 1 prob: 0.777 A9: D Skill_level: 0 prob: 0.439 A9: D Skill_level: -2 prob: 0.4 A9: A Skill_level: -1 prob: 0.302 A9: A Skill_level: -2 prob: 0.3 A9: D Skill_level: -1 prob: 0.256 A9: B Skill_level: -1 prob: 0.248 A9: C Skill_level: -1 prob: 0.248 A9: C Skill_level: -1 prob: 0.248 A9: C Skill_level: 0 prob: 0.212 A9: A Skill_level: 0 prob: 0.212 A9: A Skill_level: 0 prob: 0.205 A9: C Skill_level: 0 prob: 0.205 A9: C Skill_level: -2 prob: 0.2 A9: C Skill_level: -1 prob: 0.194 A9: D Skill_level: 0 prob: 0.144 A9: B Skill_level: 1 prob: 0.108 A9: A Skill_level: -2 prob: 0.1 A9: B Skill_level: 1 prob: 0.0684 A9: C Skill_level: 1 prob: 0.0464 A9: B Skill_level: 2 prob: 0.0289 A9: C Skill_level: 2 prob: 0.0208 A9: A Skill_level: 4 prob: 0.00833333333333 A9: C Skill_level: 2 prob: 0.0162 A9: B Skill_level: 2 prob: 0.0162 A9: B Skill_level: 2 prob: 0.0162 A9: B Skill_level: 3 prob: 0.00875273522975 A9: A Skill_level: 3 prob: 0.00875273522975 A9: A Skill_level: 3 prob: 0.00656455142231 A9: C Skill_level: 3 prob: 0.00656455142231 A9: C Skill_level: 4 prob: 0.00416666666666 A9: A
Plot of prob * Skill_level = A9


Distractor analysis plot: Item9

KEY9
D