Statistic | Type of school1 | Block C3 | Block C4 | Block C5 | Block C6 | Block C7 | Block C8 | Block C9 | Block C10 |
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† Not applicable. 1 Nonpublic school sample includes only private and Catholic schools. NOTE: The "weighted average item score" of polytomous items are 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). 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), 2010 Civics Assessment. |
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Number of scaled items | † | 20 | 17 | 18 | 19 | 18 | 18 | 19 | 19 |
Unweighted sample size | Public | 2,200 | 2,200 | 2,200 | 2,200 | 2,200 | 2,200 | 2,200 | 2,100 |
Nonpublic | 210 | 210 | 210 | 220 | 210 | 230 | 210 | 230 | |
Weighted average item score | Public | .55 | .50 | .45 | .51 | .46 | .56 | .51 | .54 |
Nonpublic | .63 | .55 | .53 | .62 | .54 | .65 | .58 | .65 | |
Weighted average polyserial | Public | .50 | .50 | .53 | .54 | .49 | .52 | .53 | .58 |
Nonpublic | .46 | .46 | .50 | .51 | .50 | .47 | .56 | .56 | |
Weighted alpha reliability | Public | .71 | .70 | .74 | .77 | .69 | .71 | .75 | .81 |
Nonpublic | .61 | .62 | .69 | .72 | .70 | .62 | .76 | .74 | |
Weighted proportion of students attempting last item | Public | .95 | .91 | .93 | .93 | .90 | .95 | .98 | .93 |
Nonpublic | .96 | .95 | .98 | .95 | .94 | .96 | .99 | .97 |