|Statistics||Multiple-choice items||Dichotomous constructed-response items||Polytomous constructed-response items|
|Number of items||35||25||21|
|Average percentage missing1||9.16||11.68||16.38|
|Minimum percentage missing1||1.12||2.13||2.50|
|Maximum percentage missing1||24.70||35.63||29.93|
|Average percentage off-task2||†||0.11||0.08|
|Minimum percentage off-task2||†||0||0|
|Maximum percentage off-task2||†||0.63||0.25|
|Average weighted proportion correct||65.03||51.41||43.03|
|† Not applicable.
1 Missing includes the categories "omitted" and "not-reached."
2 "Off-task" (constructed-response items only) is a response that is unrelated to the question and considered inappropriate.
SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2000 Reading Assessment.