In decisions between multiple alternatives with multiple attributes, the relative preference for one alternative over another often depends on other, "irrelevant" alternatives. These context effects are notoriously fragile and can disappear or even reverse depending on the way that information is presented. The fragile nature of context effects may be partly due to attentional processes. Different choice presentation formats facilitate certain types of comparisons while making other types of comparisons more difficult, thereby decreasing the likelihood of attending to the latter. For example, incommensurable attributes, such as CPU speed (GHz) and RAM size (GB) for laptops, should be more difficult to compare than attributes on a common scale, such as quality ratings. The varying levels of attention allocated to different attribute comparisons may then influence the occurrence or nonoccurrence of context effects. 

We are currently planning experiments that will leverage process tracing methods (eye-tracking and Mouselab technology) to directly test this hypothesis.