A model of verbal performance was developed which defined cognitive processes thought to underlie performance on the Word Knowledge and Paragraph Comprehension subtests of the Armed Services Vocational Aptitude Battery (ASVAB). The items from two forms of these ASVAB verbal subtests were rated on five conceptualized cognitive storage processes: (1) perceptual processing; (2) executive or control processing; (3) short term storage--lexical access semantic, and syntactic analysis; (4) long-term storage of information structures; and (5) selection and execution of the response. The relative effects of the cognitive dimensions on Rasch model item difficulties were assessed for eight groups of army applicants and personnel, using linear logistic latent trait methods. Analyses suggested that these cognitive processing variables were related to item difficulty. The logistic latent trait models predicted from 17 to 30 percent of the variance in the item difficulty values estimated by the Rasch models for the word knowledge items. However, results for the paragraph comprehension items were inconclusive. Sample test items are included. (GDC)