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CHAPTER 8: Complex Designs 263TABLE 8.4GUIDELINES FOR THE ANALYSIS OF A TWO-FACTOR EXPERIMENTNoIs the A B interaction effect significant?YesAre the main effectsof A and Bsignificant?Are the simplemain effectssignificant?No Yes No YesStop Compare Stop Comparetwo meanstwo meansand when one does not. We will illustrate both paths in Table 8.4 by describingan experiment in which there is a statistically significant interaction effect presentand then describing a study in which the interaction effect is not statisticallysignificant.Analysis Plan with an Interaction Effect• If the analysis of a complex design reveals a statistically significantinteraction effect, the source of the interaction effect is identified usingsimple main effects analyses and comparisons of two means.• A simple main effect is the effect of one independent variable at one level ofa second independent variable.In order to understand the analysis of interaction effects within a complexdesign, we will examine a contemporary approach to understanding the effectof prejudice on individuals who are stigmatized. Social psychologists suggestthat one effect of prejudice is that people who belong to stigmatized groups(e.g., ethnic minorities, gays and lesbians) develop belief systems about beingdevalued in society. With this “social-identity threat,” stigmatized individualsdevelop expectations that cause them to be especially alert to cues in theirenvironment that indicate they are viewed negatively (Kaiser, Vick, & Major,2006). This attention to cues can occur at a conscious level, in which individualsare aware of their special attention to stigma cues. More recently, however,researchers have tested the extent to which social-identity threat causespeople to be vigilant for potentially stigmatizing information without consciousawareness.One method for examining nonconscious attention is the “emotional Strooptask.” You may be familiar with the original version of the Stroop task in whichparticipants are asked to name the color in which words are printed. The Strooptask was designed to show that reading is automatic (at least for adults). Peoplefind it impossible to ignore the printed words while naming the colors. Thisautomatic-processing effect is demonstrated most dramatically in the conditionin which color words are printed in a color other than the written word (e.g.,“red” printed in blue ink). It takes participants longer to name colors in this