SAS Output

Item Characteristic Curve and Item Information Function: Item28

Plot of iif * skill_level

Distracter analysis table: Item28

The FREQ Procedure

Frequency Col Pct

Table of A28 by Skill_level
A28(A28)	Skill_level							Total
A28(A28)	-2	-1	0	1	2	3	4	Total
A	2 20.00	28 21.88	92 17.33	114 12.56	56 6.47	12 2.63	4 1.67	308
B	3 30.00	36 28.13	267 50.28	667 73.46	753 87.05	430 94.09	235 97.92	2391
C	2 20.00	36 28.13	110 20.72	95 10.46	52 6.01	14 3.06	1 0.42	310
D	3 30.00	28 21.88	62 11.68	32 3.52	4 0.46	1 0.22	0 0.00	130
Total	10	128	531	908	865	457	240	3139
Frequency Missing = 37

Distractor analysis plot: Item28

Plot of prob * Skill_level = A28

Distractor analysis plot: Item28

KEY28
B