NAEP Analysis and Scaling - IRT Parameters for the Changing Role of America in the World Scale, by Block and Item, Grade 4 U.S. History National Main Assessment (Accommodations Permitted [R3]): 2001

NAEP Analysis and Scaling → Estimation of NAEP Score Scales → NAEP Assessment IRT Parameters → U.S. History Assessment IRT Parameters → IRT Parameters for the Changing Role of America in the World Scale, by Block and Item, Grade 4 U.S. History National Main Assessment (Accommodations Permitted [R3]): 2001

NAEP Technical DocumentationIRT parameters for the changing role of America in the world scale, by block and item, grade 4 U.S. history national main assessment (accommodations permitted [R3]): 2001
Block	Item	NAEP ID	a_j	b_j	c_j	d_j1	d_j2	d_j3
H3	1	H028201	0.44	1.50	0.00	1.38	-0.62	-0.76
H4	15	H055501	1.12	1.98	0.15	†	†	†
H4	16	H055601	0.72	2.76	0.20	†	†	†
H6	10	H032201	0.97	1.01	0.26	†	†	†
H7	14	H058501	0.60	2.59	0.31	†	†	†
H8	1	H034101	0.91	0.60	0.00	2.02	-2.02	†
	5	H034501	0.67	2.98	0.00	†	†	†
	14	H035201	0.70	2.64	0.23	†	†	†
	17	H035501	0.65	1.46	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), 2001 U.S. History Assessment.

Last updated 14 July 2008 (KL)