NAEP Analysis and Scaling - Overall Descriptive Statistics for Item Blocks as Defined After Scaling, Grade 8 Reading Combined National and State Main Assessment: 2005

NAEP Analysis and Scaling → Initial Activities → Classical Item Analysis → Overall Descriptive Statistics for Item Blocks as Defined After Scaling, Grade 8 Reading Combined National and State Main Assessment: 2005

NAEP Technical DocumentationOverall descriptive statistics for item blocks as defined after scaling, grade 8 reading combined national and state main assessment: 2005
Statistic	Item type	Block R3	Block R4	Block R5	Block R6	Block R7	Block R8	Block R9	Block R10	Block R11	Block R12	Block R13	Block R14	Block R15
Number of scaled items	Total	10	9	11	12	13	11	9	12	12	10	13	10	10
	Multiple choice	3	2	7	5	6	6	5	4	3	5	4	6	6
	Dichotomously scored constructed response	4	2	3	5	6	3	2	7	8	1	1	2	0
	Polytomously scored constructed response	3	5	1	2	1	2	2	1	1	4	8	2	4
Unweighted sample size	†	24,000	24,000	24,000	24,000	24,000	24,000	24,000	24,000	24,000	24,000	16,000	24,000	24,000
Weighted average item score	†	0.42	0.55	0.69	0.57	0.69	0.72	0.65	0.57	0.68	0.67	0.65	0.73	0.79
Weighted average polyserial	†	0.69	0.62	0.72	0.63	0.72	0.66	0.75	0.62	0.68	0.72	0.59	0.71	0.69
Weighted alpha reliability	†	0.76	0.69	0.77	0.70	0.78	0.68	0.71	0.73	0.77	0.78	0.72	0.70	0.67
Weighted proportion of students attempting last item¹	†	0.83	0.86	0.95	0.88	0.85	0.96	0.92	0.78	0.89	0.96	0.94	0.87	0.96
† Not applicable. ¹ The "Weighted proportion of students attempting last item" is equal to 1 - (Percent not responding to last item /100). NOTE: Item statistics in this table are described on the page Blocks of Items. SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2005 Reading Assessment.

Last updated 17 February 2010 (GF)