Validating hierarchical sequences in the design copying domain using latent trait models.

Abstract

The present study was a systematic investigation of hierarchical skill sequences in the design copying domain. The factors associated with possible variations in task difficulty were delineated. Five hierarchies were developed to reflect variations in rule usage, the structuring of responses, presence of angles, spatial orientations, and stimulus complexity. Three-hundred thirty four subjects aged five through ten years were administered a 25 item design copying test. The data were analyzed using probabilistic models. Latent trait models were developed to test the hypothesized skill sequences. Each latent trait model was statistically compared to alternate models to arrive at a preferred model that would adequately represent the data. Results suggested that items with predictable difficulty levels can be developed in this domain based on an analysis of stimulus dimensions and the use of rules for task completion. The inclusion of visual cues to guide design copying assists accurate task completion. Implications of the current findings for facilitating the construction of tests which accurately provide information about children's skill levels were discussed. The presence of hierarchical skill sequences in a variety of ability domains was supported.