Despite historical emphasis on "specific" learning disabilities (SLDs), academic skills are strongly correlated across the curriculum. Thus, one can ask how specific SLDs truly are. To answer this question, we used bifactor models to identify variance shared across academic domains (academic "g"), as well as variance unique to…

Two models are considered for how people verify explicitly quantified sentences. To test the models, three reaction time experiments required subjects to verify statements quantified by some or all. The results show that some-statements took longer to verify than all-statements. (Author/DEP)