Comparison of Kernel equating methods under NEAT and NEC designs

Abstract

In this study, Kernel test equating methods were compared under NEAT and NEC designs. In NEAT design, Kernel post-stratification and chain equating methods taking into account optimal and large bandwidths were compared. In the NEC design, gender and/or computer/tablet use was considered as a covariate, and Kernel test equating methods were performed by using these covariates and considering bandwidths. The study shows that, in the NEAT design, Kernel chain equating methods exhibit higher error than the post-stratification equating methods do since the lowest error in the NEC design was obtained from the Kernel equating method with large bandwidth through the computer/tablet variable. Kernel test equating results based on the NEC design, which considers gender and computer tablet use variables as a covariate separately, showed lower SEE than that of the NEC pattern, which takes these variables together as covariates. In terms of the bandwidth, when all methods are compared within the pattern used (i.e., NEAT and NEC), it has been seen that generally Kernel test equating with large bandwidth results in fewer errors than the Kernel test equating with optimal bandwidth. When the NEAT and NEC designs are compared generally, the NEAT design has a lower SEE than that of the NEC design.