skip to main content skip to footer

The Impact of Anchor Test Length on Equating Results in a Nonequivalent Groups Design KE NEAT

Author(s):
Ricker, Kathryn L.; von Davier, Alina A.
Publication Year:
2007
Report Number:
RR-07-44
Source:
ETS Research Report
Document Type:
Report
Page Count:
19
Subject/Key Words:
Kernel Equating (KE), Non-Equivalent-Groups Anchor Test (NEAT) Design, Equipercentile Equating, Equating Bias, Anchor Tests, Test Length

Abstract

square error of the differences (RMSE) were used as measures to compare the methods to the criterion equating, which in this study is an equivalent groups (EG) equipercentile equating function. The results indicate that bias tended to increase in the conversions as the anchor test length decreased, but the KE PSE with optimal bandwidths and equipercentile (frequency estimation) methods were less sensitive to this change than the other methods. The KE PSE linear method with large bandwidths performed poorly compared to the criterion across all anchor test lengths.

Read More