Table 2.

Item difficulty, standard error, fit and point-measure correlation

Entry Number	Item Difficulty	Model Standard Error	Infit		Outfit		PT- measure
			MNSQ	ZSTD	MNSQ	ZSTD
1	1.67	0.23	1.32	3.8	1.62	3.8	0.05
13	1.66	0.22	1.15	1.9	1.4	3.1	0.24
26	1.64	0.21	1.09	1.2	1.37	2.9	0.29
16	1.54	0.21	1.2	3.6	1.31	3.4	0.22
27	1.54	0.2	1.08	1.5	1.17	1.9	0.32
5	1.54	0.2	1.06	1.1	1.16	1.9	0.34
6	1.55	0.19	1.06	1.1	1.15	1.6	0.33
3	1.64	0.19	0.98	− 0.2	1.09	0.8	0.4
11	1.58	0.18	1.02	0.3	1.05	0.5	0.39
17	1.65	0.18	1.04	0.6	0.99	0	0.38
21	1.56	0.18	1.04	0.7	0.99	0	0.37
9	1.62	0.17	1.02	0.3	1	0	0.36
2	1.97	0.17	1	0.1	0.92	− 0.3	0.31
15	1.6	0.16	0.96	− 0.5	0.99	− 0.1	0.43
20	1.54	0.17	0.99	− 0.2	0.96	− 0.4	0.41
23	1.63	0.16	0.91	-1.3	0.99	− 0.1	0.43
8	1.54	0.15	0.97	− 0.5	0.94	− 0.7	0.43
24	1.63	0.15	0.95	− 0.9	0.91	-1	0.45
19	1.75	0.15	0.92	-1	0.94	− 0.3	0.41
10	1.63	0.14	0.94	− 0.8	0.9	− 0.8	0.42
12	1.54	0.13	0.93	-1.4	0.88	-1.5	0.47
18	1.65	0.12	0.91	− 0.7	0.72	-1.2	0.39
22	1.69	0.12	0.9	-1.3	0.8	-1.5	0.45
4	1.9	0.13	0.9	− 0.9	0.84	− 0.7	0.4
14	1.54	0.13	0.87	-2	0.83	-2.1	0.52
25	1.68	0.14	0.87	-1.8	0.79	-1.6	0.48
7	1.8	0.15	0.85	-1.7	0.73	-1.7	0.47
28	1.9	0.15	0.83	-1.6	0.71	-1.5	0.46
Mean	1.66	0.16	0.99	0	1.01	0.2
SD	0.14	0.03	0.11	1.5	0.21	1.6

MNSQ (mean square residual)

ZSTD (standardised mean square residual)

SD (standard deviation)