Abstract
Bloom's taxonomy is a classification of learning objectives originally developed for general educational purposes. The taxonomy was revised to expand beyond cognitive processes and to include knowledge types as an orthogonal dimension. As Bloom's taxonomy is a tool widely used in biology education by researchers and instructors, it is important to examine the underlying assumptions embedded within how people may implicitly understand and use the taxonomy. In this paper, we empirically examine two major assumptions: the independence of the knowledge-type and cognitive-process dimensions and the use of action verbs as proxies for different cognitive processes. Contingency analysis on 940 assessment items revealed that the knowledge-type and cognitive-process dimensions are related and not independent. Subsequent correspondence analysis identified two principle axes in how the two dimensions are related, with three clusters of knowledge types and cognitive processes. Using the Shannon evenness index, we did not find a clear relationship between question prompt words (including action verbs) and cognitive processes in the assessment items. Based on these results, we suggest that both dimensions of the revised Bloom's taxonomy should be used and that question prompt words or action verbs alone are not sufficient in classifying the embedded learning objectives within assessment items.