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NAEP Analysis and Scaling → Estimation of NAEP Score Scales → NAEP Assessment IRT Parameters → Mathematics Assessment IRT Parameters → IRT Parameters for Items in the Measurement Subscale, Grade 4 Mathematics Combined National and State Assessment, by Item and Block: 2015

NAEP Technical DocumentationIRT Parameters for Items in the Measurement Subscale, Grade 4 Mathematics Combined National and State Assessment, by Item and Block: 2015

IRT parameters for items in the measurement subscale, grade 4 mathematics combined national and state assessment, by item and block: 2015
Block	Item	NAEP ID	a_j	b_j	c_j	d_j1	d_j2	d_j3	d_j4
M3	2	M340601	0.83	-1.62	0.07	†	†	†	†
	5	M341401	0.85	-0.81	0.04	†	†	†	†
	8	M340801	0.81	0.70	†	0.41	-0.41	†	†
	11	M3424CL	0.40	-0.52	†	0.55	2.29	-6.53	3.69
	15	M341501	1.07	0.97	†	†	†	†	†
M4	5	M147101	1.11	0.73	0.14	†	†	†	†
M5	5	M218601	0.69	-1.44	0.09	†	†	†	†
	9	M219001	0.51	-2.01	0.13	†	†	†	†
	13	M219401	0.81	-1.86	0.10	†	†	†	†
M6	2	M344501	0.75	-1.58	0.15	†	†	†	†
M6	11	M343801	1.47	1.17	0.20	†	†	†	†
M7	1	M347701	0.47	-2.20	0.13	†	†	†	†
	6	M347401	0.78	-1.28	0.13	†	†	†	†
	9	M347201	0.39	-1.43	0.13	†	†	†	†
	14	M230301	1.27	0.32	†	†	†	†	†
M8	3	M230001	0.64	0.20	0.19	†	†	†	†
M8	15	M240401	0.83	1.45	†	†	†	†	†
M9	1	M226901	1.15	0.80	0.28	†	†	†	†
M9	9	M338501	0.74	-0.91	0.10	†	†	†	†
M10	3	M219901	0.54	0.18	0.19	†	†	†	†
	8	M220401	0.45	0.97	†	-4.32	4.32	†	†
	15	M221101	0.87	0.38	†	0.23	-0.23	†	†
M11	2	M156301	0.58	-2.08	0.15	†	†	†	†
	7	M158301	1.04	0.71	0.20	†	†	†	†
	11	M161901	0.35	-1.40	†	0.28	-0.28	†	†
M12	4	M339101	0.60	0.85	0.15	†	†	†	†
M12	10	M339201	0.95	0.02	0.16	†	†	†	†
† Not applicable; c parameters are not estimated for the two-parameter logistic model or generalized partial credit models, and d parameters are not estimated for two-parameter or three-parameter logistic models. NOTE: For item j, a_j represents the discriminatory power of the item, b_j represents a location parameter related to item difficulty, c_j represents the guessing parameter, and d_ji represents the category threshold parameter for category i. The c parameter value is assumed to be exactly zero and is not estimated for items scaled with the two-parameter logistic model. For item j, d_ji may not sum to zero because of rounding. SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2015 Mathematics Assessment.

Last updated 17 November 2021 (ML)

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