Table of Contents | Search Technical Documentation | References
Statistic | Item type | Block M21 | Block M22 | Block M23 | Block M24 | Block MX51 | Block MX52 |
---|---|---|---|---|---|---|---|
Number of scaled items | Total | 23 | 22 | 35 | 35 | 23 | 22 |
Multiple choice | 19 | 17 | 25 | 30 | 18 | 17 | |
Dichotomously scored constructed response | 4 | 5 | 10 | 5 | 5 | 5 | |
Polytomously scored constructed response | 0 | 0 | 0 | 0 | 0 | 0 | |
Unweighted sample size | † | 3,800 | 3,800 | 3,800 | 3,700 | 3,800 | 3,700 |
Weighted average item score | † | 0.67 | 0.69 | 0.66 | 0.69 | 0.65 | 0.68 |
Weighted average polyserial | † | 0.72 | 0.65 | 0.67 | 0.63 | 0.69 | 0.67 |
Weighted alpha reliability | † | 0.89 | 0.82 | 0.91 | 0.89 | 0.87 | 0.84 |
Weighted proportion of students attempting last item1 | † | 0.93 | 0.97 | 0.87 | 0.74 | 0.93 | 0.98 |
† 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), 2004 Mathematics Long-Term Trend Assessment. |