NAEP Analysis and Scaling - IRT Parameters for the Data Analysis, Statistics, and Probability Scale, by Block and Item, Grade 4 Mathematics National Main Assessment (Accommodations Permitted [R3]): 2000

NAEP Analysis and Scaling → Estimation of NAEP Score Scales → NAEP Assessment IRT Parameters → Mathematics Assessment IRT Parameters → IRT Parameters for the Data Analysis, Statistics, and Probability Scale, by Block and Item, Grade 4 Mathematics National Main Assessment (Accommodations Permitted [R3]): 2000

NAEP Technical DocumentationIRT parameters for the data analysis, statistics, and probability scale, by block and item, grade 4 mathematics national main assessment (accommodations permitted [R3]): 2000
Block	Item	NAEP ID	a_j	b_j	c_j	d_j1	d_j2	d_j3	d_j4
M3	11	M040001	0.85	0.14	0.00	†	†	†	†
M3	12	M040101	0.67	-0.05	0.20	†	†	†	†
M4	5	M017801	0.75	0.48	0.15	†	†	†	†
M5	10	M066901	0.27	0.66	0.00	-1.31	-2.01	2.14	1.19
M6	6	M020201	0.72	-0.34	0.00	†	†	†	†
M8	11	N250231	1.15	-0.00	0.19	†	†	†	†
M9	10	M091401	0.41	1.42	0.00	-2.40	2.30	0.33	-0.23
M11	7	M046601	1.15	0.44	0.00	†	†	†	†
	11	M047001	1.34	1.65	0.18	†	†	†	†
	14	M047301	1.39	-0.43	0.00	†	†	†	†
M12	2	M086501	0.87	-0.81	0.18	†	†	†	†
M13	6	M043101	1.26	0.43	0.26	†	†	†	†
M13	7	M043201	0.73	-0.93	0.00	†	†	†	†
M14	6	M072301	0.57	-0.39	0.19	†	†	†	†
† Not applicable; the number of item parameters estimated depends upon the IRT model used for scaling. 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 is the category threshold parameter for category i. The c-parameter value is exactly zero for items scaled with the two-parameter logistic model or the generalized partial credit model. SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2000 Mathematics Assessment.

Last updated 14 July 2008 (KL)