NAEP Analysis and Scaling - Overall Descriptive Statistics for Items as Defined After Scaling, Grade 4 Reading Combined National and State Main Assessment: 2007

NAEP Analysis and Scaling → Initial Activities → Classical Item Analysis → Overall Descriptive Statistics for Items as Defined After Scaling, Grade 4 Reading Combined National and State Main Assessment: 2007

NAEP Technical DocumentationOverall descriptive statistics for items as defined after scaling, grade 4 reading combined national and state main assessment: 2007
Statistic	Item type	Block R3	Block R4	Block R5	Block R6	Block R7	Block R8	Block R9	Block R10	Block R11	Block R12
† 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), 2007 Reading Assessment.
Number of scaled items	Total	10	10	11	9	10	10	10	10	10	10
	Multiple choice	6	6	7	4	5	6	5	6	6	6
	Dichotomously scored constructed response	0	2	3	2	1	0	3	1	2	2
	Polytomously scored constructed response	4	2	1	3	4	4	2	3	2	2
Unweighted sample size	†	38,200	37,900	37,600	37,900	38,000	38,000	38,400	38,000	38,000	38,000
Weighted average item score	†	0.67	0.72	0.47	0.65	0.51	0.59	0.78	0.64	0.77	0.64
Weighted average polyserial	†	0.68	0.77	0.60	0.71	0.62	0.70	0.71	0.66	0.76	0.69
Weighted alpha reliability	†	0.74	0.79	0.72	0.76	0.70	0.76	0.73	0.75	0.71	0.74
Weighted proportion of students attempting last item¹	†	0.87	0.83	0.77	0.72	0.81	0.80	0.83	0.82	0.90	0.86

Last updated 02 March 2010 (JL)