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NAEP Analysis and Scaling → Initial Activities → Classical Item Analysis → Overall Descriptive Statistics for Item Blocks as Defined After Scaling, Grade 4 Reading Combined National and State Assessment, by Block: 2019
NAEP Technical DocumentationOverall Descriptive Statistics for Item Blocks as Defined After Scaling, Grade 4 Reading Combined National and State Assessment, by Block: 2019
| Statistic | Block R1 | Block R2 | Block R3 | Block R4 | Block R5 | Block R6 | Block R7 | Block R8 | Block R9 | Block R10 | Block R14 | Block R15 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| The "Weighted average item score" of polytomous items is standardized to have a scale of 0 to 1 so they are comparable to dichotomously scored items. | ||||||||||||
| The "Weighted proportion of students attempting last item" is equal to 1 – (Percent not responding to last item / 100). Weights are applied to reflect sampling design. | ||||||||||||
| CR = Constructed response. Item statistics in this table are described on the page Blocks of Items. | ||||||||||||
| U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2019 Reading Assessment. | ||||||||||||
| Total number of scaled items | 11 | 8 | 10 | 10 | 9 | 10 | 10 | 10 | 9 | 10 | 9 | 11 |
| Number of multiple-choice items | 8 | 5 | 7 | 7 | 5 | 7 | 7 | 6 | 5 | 6 | 3 | 7 |
| Number of dichotomously scored CR items | 1 | 1 | 0 | 0 | 1 | 0 | 1 | 0 | 1 | 1 | 3 | 1 |
| Number of polytomously scored CR items | 2 | 2 | 3 | 3 | 3 | 3 | 2 | 4 | 3 | 3 | 3 | 3 |
| Unweighted sample size | 24,700 | 25,400 | 24,900 | 24,900 | 24,800 | 24,600 | 25,800 | 24,900 | 24,800 | 24,400 | 24,700 | 24,800 |
| Weighted average item score | .65 | .58 | .52 | .53 | .52 | .45 | .55 | .47 | .48 | .52 | .46 | .53 |
| Weighted average R biserial/polyserial | .69 | .70 | .72 | .70 | .69 | .67 | .65 | .71 | .65 | .62 | .63 | .72 |
| Weighted alpha reliability | .77 | .71 | .78 | .75 | .75 | .75 | .73 | .78 | .71 | .69 | .66 | .80 |
| Weighted proportion of students attempting last item | .92 | .84 | .88 | .87 | .90 | .86 | .81 | .87 | .85 | .77 | .64 | .92 |
Last updated 05 October 2023 (SK)