The following summary tables give the upper 99.8 percent confidence limit for the error rates for each of the instruments as well as the sampling information. The 99.8 percent confidence limit and the selection rates indicated were chosen to make these results comparable to those of administrations since 1983, all of which used the same parameters. There were no teacher or school questionnaires administered with the long-term trend assessment, and no teacher questionnaires were administered with the arts assessment.
Assessment | Age/grade | Number of samples | Selection rate | Number of different booklets | Number of booklets sampled | Number of fields sampled | Number of errors | Observed error rate | Upper 99.8% confidence limit |
---|---|---|---|---|---|---|---|---|---|
SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2008 Long-Term Trend and 2008 Arts Assessments. | |||||||||
Mathematics Long-Term Trend (LTT) | Age 9 | 8,866 | 1/633 | 7 | 14 | 1,310 | 0 | 0.0000 | 0.0047 |
Age 13 | 8,734 | 1/672 | 7 | 13 | 1,371 | 0 | 0.0000 | 0.0045 | |
Age 17 | 9,902 | 1/900 | 6 | 11 | 1,261 | 1 | 0.0008 | 0.0067 | |
Reading Long-Term Trend (LTT) | Age 9 | 8,923 | 1/223 | 20 | 40 | 2,648 | 1 | 0.0004 | 0.0032 |
Age 13 | 8,767 | 1/219 | 20 | 40 | 3,040 | 0 | 0.0000 | 0.0020 | |
Age 17 | 9,963 | 1/249 | 20 | 40 | 3,032 | 1 | 0.0003 | 0.0028 | |
Visual arts | Grade 8 | 4,003 | 1/250 | 8 | 16 | 440 | 0 | 0.0000 | 0.0140 |
Music | Grade 8 | 4,028 | 1/252 | 8 | 16 | 720 | 0 | 0.0000 | 0.0086 |
Grade | Total samples | Selection rate | Different booklets | Number of booklets sampled | Number of fields sampled | Number of errors | Observed error rate | Upper 99.8% confidence limit |
---|---|---|---|---|---|---|---|---|
SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2008 Arts Assessment. | ||||||||
8 | 579 | 1/116 | 1 | 5 | 895 | 2 | 0.0022 | 0.0116 |
Accommodation | Instrument | Total samples | Selection rate | Different booklets | Number of booklets sampled | Number of fields sampled | Number of errors | Observed error rate | Upper 99.8% confidence limit |
---|---|---|---|---|---|---|---|---|---|
SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2008 Long-Term Trend and 2008 Arts Assessments. | |||||||||
Students with disabilities (SD) | Long-Term Trend | 2,070 | 1/518 | 1 | 4 | 248 | 0 | 0.0000 | 0.0247 |
Arts | 1,053 | 1/263 | 1 | 4 | 256 | 2 | 0.0078 | 0.0400 | |
English language learners (ELL) | Long-Term Trend | 1,926 | 1/482 | 1 | 4 | 168 | 0 | 0.0000 | 0.0363 |
Arts | 645 | 1/161 | 1 | 4 | 176 | 0 | 0.0000 | 0.0347 |