Hаllie hypоthesized thаt intrоducing tаblet cоmputers to the classroom would increase student learning and achievement. After analyzing their data, Hallie found that usage of tablet computers actually led to declines in student performance. When Hallie submitted their research for publication, they reported that they had hypothesized that tablet computers would interfere with student learning because of their potential to distract students. In this example, Hallie has: