Coleman and Wu (2009) emphasized the similarities between the hierarchy of effects theory and agenda-setting theory, and how the latter can be used to analyze the former. The hierarchy of effects theory has three components: knowledge, attitude, and behavior, also known as "learn, feel, do." The first level of agenda-setting, such as a policy issue gaining public attention, corresponds to the "knowledge" component of the hierarchy of effects theory. The second level of agenda-setting, such as how the public views or feels about a policy issue, corresponds to the "attitude" component. Coleman and Wu's study is not so much focused on the order of these components, but instead on which component, knowledge (level one) and attitude (level two), has a greater effect on public behavior.