Contrast and assimilation effects of processing fluency

As processing difficulty associated with a product increases, information about a subsequently encountered product becomes easier to process, leading to more favorable evaluations of it (a contrast effect). If, however, the two products are categorized as part of the same overall experience, then the negative feelings elicited by increased processing difficulty of the first product transfer to the second product, leading to more unfavorable evaluations of it (an assimilation effect). Five studies identify the conditions in which the two processes occur and outline the various mechanisms that might underlie these effects.