Table 3.

Item fit statistics.

Item #	Infit MNSQ	Infit ZSTD	Outfit MNSQ	Outfit ZSTD	PTMZ R corr.	Difficulty scores
CH
1	1.08	4.35	1.08	4.05	0.62	−0.04
6	0.87	−7.97	0.87	−7.49	0.65	−0.25
12	1.07	4.38	1.17	9.61	0.62	−0.69
17	1.21	9.48	1.16	7.70	0.54	0.74
27	0.83	−9.40	0.81	−9.90	0.61	0.23
PI
2	1.11	6.68	1.22	9.90	0.59	−0.59
3	1.08	3.91	0.93	−3.05	0.48	1.28
21	1.06	3.39	1.19	9.87	0.55	−0.26
29	0.99	−0.74	1.08	4.35	0.60	−0.43
31	0.79	−9.90	0.79	−9.90	0.61	0.09
36	1.04	1.92	1.05	2.56	0.59	−0.09
PO
4	0.94	−3.63	0.96	−2.22	0.66	0.29
10	0.85	−8.98	.84	−9.35	0.67	0.44
13	1.09	5.42	1.17	9.14	0.62	−0.06
14	0.89	−7.02	0.86	−8.06	0.71	0.16
15	1.37	9.90	1.59	9.90	0.61	−1.23
20	0.82	−9.90	0.82	−9.90	0.69	0.29
28	1.08	4.46	1.08	4.49	0.66	0.10
JU
7	1.03	1.74	1.17	9.51	0.62	−0.50
11	1.03	1.67	1.17	9.53	0.65	−0.57
16	1.05	2.75	1.06	2.97	0.63	0.02
25	1.13	5.74	1.03	1.55	0.57	0.76
26	0.94	−2.92	0.93	−3.55	0.66	0.10
35	0.93	−3.79	0.89	−5.71	0.64	0.19
CN
5	1.12	7.87	1.12	7.54	0.63	0.16
8	0.84	−9.90	0.85	−9.90	0.70	−0.54
18	1.40	9.90	1.44	9.90	0.54	0.17
19	0.77	−9.90	0.82	−9.90	0.67	−0.34
30	1.02	1.50	0.98	−1.29	0.63	0.57
34	0.86	−9.90	0.90	−6.96	0.67	−0.02
EN
9	0.99	−0.26	1.09	3.74	0.69	−0.28
22	1.07	2.79	0.98	−1.02	0.69	0.55
23	1.05	1.83	0.92	−3.17	0.71	0.37
24	1.13	5.32	1.16	6.42	0.70	−0.27
32	1.07	3.18	1.27	9.90	0.68	−0.65
33	0.79	−8.99	0.70	−9.90	0.74	0.28

Note. MNSQ: mean-square; ZSTD: standardized weighted (infit) and unweighted (outfit) mean-squared fit statistics; PTMZ: point-measure correlation.