NAEP Analysis and Scaling → Estimation of NAEP Score Scales → NAEP Assessment IRT Parameters → IRT Parameters for the Mathematics Long-Term Trend Assessments → IRT Parameters for Single Overall Scale, Age 13 Mathematics Long-Term Trend Assessment, by Item and Block: 2012

NAEP Technical DocumentationIRT parameters for single overall scale, age 13 mathematics long-term trend assessment, by item and block: 2012

Block	Item	NAEP ID	aj	bj	cj
† Not applicable; c parameters are not estimated for generalized partial credit models. NOTE: For item j, aj represents the discriminatory power of the item, bj represents a location parameter related to item difficulty, and cj represents the guessing parameter. The c parameter value is exactly zero for items scaled with the two-parameter logistic model. SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2012 Mathematics Long-Term Trend Assessment.
MA	1	N299801	1.14	0.28	0.29
	2	N299901	0.50	-2.40	0.11
	3	N300001	1.28	-1.58	0.21
	4	N300101	0.38	-3.28	0.15
	5	N300201	1.27	-0.46	†
	6	N300301	1.75	-0.22	0.21
	7	N300401	0.91	0.11	†
	8	N292301	0.84	-0.79	0.35
	9	N292401	0.33	-2.66	†
	10	N292501	0.96	-0.46	0.30
	11	N292601	0.76	-1.32	0.21
	12	N300501	0.94	0.14	†
	13	N300601	0.41	-2.21	0.26
	14	N300701	1.25	-0.45	0.14
	15	N300801	1.15	-0.49	0.19
	16	N300901	1.74	-0.12	0.17
	17	N301001	0.79	1.01	0.17
	18	N301101	0.67	-0.67	0.32
	19	N301201	1.01	-0.83	0.27
	20	N301301	0.85	0.47	0.15
	21	N301401	0.75	-0.55	0.10
	22	N301501	0.79	-2.26	†
	23	N301601	0.93	0.40	0.29
MA	1	N336201	1.80	0.10	0.26
	2	N334201	0.49	-3.91	†
	3	N335301	0.80	0.80	0.04
	4	N333701	1.13	0.26	†
	5	N335401	0.67	-1.98	0.21
	6	N335201	0.78	-0.31	0.23
	7	N334101	1.05	0.83	0.36
	8	N334301	0.62	-0.68	0.39
	9	N336501	0.92	-0.74	0.11
	10	N329201	0.68	-2.12	†
	11	N334801	0.40	-0.54	0.27
	12	N331501	0.80	-0.35	†
	13	N332301	0.95	-0.65	0.26
	14	N334401	0.80	0.74	0.33
	15	N337201	0.73	-1.09	0.35
	16	N333401	1.40	-0.40	†
	17	N334901	0.93	-1.16	0.19
	18	N336601	0.96	-0.40	0.19
	19	N335701	0.79	-1.08	0.20
	20	N330101	0.77	-0.32	0.25
	21	N330102	0.92	-0.04	0.27
	22	N336401	0.98	0.39	0.42
	23	N358101	1.31	0.05	0.16
	24	N336101	0.98	1.11	0.13
MB	1	N301701	0.88	-1.61	0.22
	2	N301801	0.40	-4.91	†
	3	N301901	0.52	-1.31	0.07
	4	N302001	0.94	0.04	0.12
	5	N302101	0.89	-0.84	0.27
	6	N302201	0.76	-0.99	0.18
	7	N302301	0.55	-2.97	0.28
	8	N294601	0.67	-2.34	0.12
	9	N294701	0.36	-3.74	0.15
	10	N294801	0.77	0.19	0.16
	11	N294901	0.87	-0.85	0.34
	12	N302401	1.17	-0.60	†
	13	N302501	0.89	0.41	0.07
	14	N302601	0.95	0.33	†
	15	N302701	0.91	-0.59	0.13
	16	N302801	0.85	-0.37	0.36
	17	N302901	0.70	-2.07	†
	19	N303101	0.68	-0.40	0.18
	20	N303201	0.94	-0.04	†
	21	N303301	0.93	-1.05	0.11
	22	N303401	0.96	-0.29	0.16
	23	N303501	1.02	0.63	0.65
MC	1	N324101Y	0.44	-2.12	0.10
MC	2	N324201	0.70	-1.40	0.18
	3	N324301	0.91	-0.02	†
	4	N324401	1.20	-0.13	0.20
	5	N322401	0.54	-1.60	†
	6	N322501	1.26	-0.03	0.18
	7	N322601	0.50	-3.01	0.14
	8	N322602	0.91	-0.49	0.07
	9	N324501	0.75	0.18	0.16
	10	N324601	1.67	0.15	0.21
	11	N324701	1.18	-0.11	0.20
	12	N324801	1.31	-0.26	0.11
	13	N324901	1.22	-0.97	0.17
	14	N325001	0.66	-0.96	†
	15	N325101	0.79	-1.09	0.22
	16	N325201	0.55	-0.53	0.23
	17	N325301	0.71	-1.83	†
	18	N325401	1.03	-0.10	0.24
	19	N325501	1.66	0.48	0.12
	20	N325601	0.60	-1.29	†
	21	N325701	1.61	0.76	†
	22	N325801	1.02	-0.65	0.11
	23	N326001	0.63	-0.72	†
	24	N326101	0.83	-0.42	0.22
	25	N326201	1.05	-0.73	0.07
	26	N326301	1.09	-0.08	0.23
	27	N326401	0.37	-2.20	†
MD	1	N310501	0.56	-4.09	0.14
	2	N316601	0.49	-4.13	†
	3	N316602	0.46	-4.35	†
	4	N316603	0.58	-2.64	†
	5	N312701	0.61	-4.33	0.23
	6	N312702	0.59	-4.31	0.24
	7	N310801	0.33	-4.29	0.14
	8	N310802	0.93	-1.13	0.15
	9	N310803	0.43	-3.23	0.09
	10	N316701	0.70	-2.30	†
	11	N310901	0.64	-1.70	0.31
	12	N316801	0.71	-1.46	0.22
	13	N316901	0.66	-1.52	0.30
	14	N316902	1.13	0.95	0.07
	15	N317001	0.50	-0.44	0.34
	16	N317101	0.94	-0.35	†
	17	N317102	0.94	-0.45	†
	18	N317103	1.09	0.11	†
	19	N312001	0.97	-1.04	0.21
	20	N317201	1.04	-0.57	0.21
	21	N317301	1.15	0.18	0.23
	22	N317401	0.74	-0.05	0.14
	23	N317501	0.99	-0.07	0.05
	24	N317601	1.67	-0.02	0.20
	25	N317701	1.31	-0.26	0.22
	26	N317801	1.30	0.16	0.19
	27	N317901	0.86	-0.58	0.30
	28	N318001	0.73	-1.08	0.18
	30	N318201	0.54	-0.18	0.14
MD	31	N318301Y	0.40	0.77	0.24
MD	31	N318301Z	0.37	0.22	0.17
MD	32	N318401	0.84	1.13	0.10
	33	N314001	1.31	0.37	0.27
	34	N318501	1.11	0.37	0.21
	35	N318601	1.55	0.45	0.23
	36	N318701	1.09	0.32	0.09
	37	N318801	0.86	1.02	†
ME	1	N296201	0.88	-1.50	0.24
	2	N296301	0.50	-2.40	0.10
	3	N296401	0.89	0.06	†
	4	N296501	1.48	-0.31	0.09
	5	N287801	0.61	-3.71	0.16
	6	N287901	0.51	-3.93	0.22
	7	N288001	0.64	-1.72	0.22
	8	N288101	0.32	-2.89	†
	9	N288201	1.09	-0.90	0.35
	10	N296601	0.61	-0.50	0.30
	11	N296701	0.79	0.35	†
	12	N296801	1.08	1.11	0.44
	13	N296901	1.06	-1.07	†
	14	N297001	1.50	0.30	†
	15	N297101	1.21	0.15	0.16
	16	N297201	1.44	0.11	0.25
	17	N297301	1.94	0.63	0.15
	18	N297401	1.97	0.99	0.14
	19	N297501	1.23	0.49	0.28
	20	N297601	2.17	0.50	0.45
	21	N297701	1.28	0.36	0.11
	22	N297801	1.77	0.89	0.16
	23	N297901	2.07	1.08	0.20
MF	1	N298001	1.53	-0.21	0.11
	2	N298101	0.77	-0.60	0.21
	3	N298201	0.91	-0.11	†
	4	N298301	1.48	-0.28	0.67
	5	N289901	0.42	-4.56	†
	6	N290001	0.79	-2.38	0.28
	7	N290101	0.70	-1.00	†
	8	N290201	0.77	-2.37	0.09
	9	N290301	1.81	-0.48	0.13
	10	N298401	1.01	-0.29	0.27
	11	N298501	0.67	-0.77	0.26
	12	N298601	0.94	-0.77	†
	13	N298701	1.21	0.08	0.23
	14	N298801	1.32	0.44	0.21
	15	N298901	2.24	0.92	0.28
	16	N299001	0.73	-0.60	†
	17	N299101	0.70	-3.27	0.15
	18	N299201	1.01	0.28	0.11
	19	N299301	1.94	-0.06	0.12
	21	N299501	1.69	0.74	0.19
	22	N299601	1.02	0.16	0.32
	23	N299701	1.14	-0.24	0.36

Printer-friendly Version