ATI research uses advanced statistical procedures to address assessment goals associated with standards-based education. One research focus includes statistical analyses of items and assessments. Item Response Theory (IRT) a statistical analysis procedure, makes it possible to place scores from different assessments on a common scale. If IRT were not used, a difference in scores between two tests could be due to differences in test difficulty or changes in student achievement, or both. IRT considers both item difficulty and achievement level making it possible to produce an ability score and to measure academic progress. This cannot be accomplished by assessments that provide only raw data (percent/number correct).
ATI routinely provides psychometric analyses of ATI and district developed assessments that have been administered to a group of students large enough to support such analyses. Item analysis uses IRT techniques to determine item parameter estimates and assessment reliability. Access to a variety of statistical information is available through the Galileo K-12 Online Item Analysis and Item Parameter reports.
ATI also utilizes categorical data analysis procedures to determine the risk of not meeting standards. Categorical data analysis techniques informed development of the Galileo Risk Assessment Report. The report classifies students with respect to their risk of failing to show mastery on the statewide test based on their performance on one or more district -wide assessments. Structural equation modeling is also used to identify variables that impact learning. Investigations using structural equation modeling have revealed the effects of student learning at different points throughout the year on performance on the statewide test. Finally, value-added modeling is used to identify factors affecting learning.
For more information on how ATI can support your district or charter with a comprehensive instructional improvement and instructional effectiveness system designed to promote student learning, contact us today.