LINKING STATEWIDE TESTS TO THE NATIONAL ASSESSMENT OF EDUCATIONAL-PROGRESS - ACCURACY OF COMBINING TEST-RESULTS ACROSS STATES

The National Assessment of Educational Progress (NAEP) surveys achieve ment at selected grades and content areas and does not report scores a t the individual, school, or district level. There is a desire by scho ols and school districts to compare results of their own assessments t o the national results provided by NAEP. The main objective of this st udy is to investigate the accuracy of linking NAEP scores to statewide test results. This study investigates whether the population invarian ce condition of the function for linking two sets of scores holds, spe cifically whether the function obtained for an individual state is the same as the function obtained for other states either individually or combined. Using an equipercentile procedure, functions obtained separ ately for four states are compared to a function obtained using data c ombined across the four states. The results suggest that the link betw een statewide tests and the NAEP does not provide precise information and that the information from a linking study such as this one should be limited to rough estimates of percentages of students in each of th e NAEP achievement levels. Two areas of concern are identified: (a) th e differences between the statewide tests and the NAEP test and (b) th e error due to results from the two sets of tests and the error due to the linking analyses.