Recently, researchers tested how makeup affects people's impressions of women. Here is how the story was covered by ABC News–the story includes a video.

In the study, a set of female targets posed for photos in which they were wearing no makeup, some makeup, professional makeup, or full, "glamour" makeup. Then the photos were rated by a large number of observers. You can read about the details of the study on the ABC News website.

The results showed that for the most part, women wearing makeup were rated more positively on all four ratings. Here are some quotes from the lead researcher:

"We found that when faces were shown very quickly, all ratings went up with cosmetics in all different looks," said Nancy Etcoff…. "The women were judged as more competent, likable, attractive and trustworthy."

When the photos were shown more slowly, the results were a little bit different:

"When they got to the more dramatic makeup looks, people saw them as equally likable and much more attractive and competent, but less trustworthy," Etcoff said. "Dramatic makeup was no longer an advantage compared to when people saw the photos very quickly."

Here are some questions about the study:

a.) Consider only the study in which participants viewed the photos for 250 ms. What were the independent and dependent variables in this study? Was the independent variable between-subjects or within subjects?

b.) Sketch a graph of the results of the 250ms study. What is the best way to graph these results?

c.) Is this study an experiment? Does it support the causal claim in the headline, "Makeup makes women seem more competent"?

d. ) Why did the authors conduct the study under two conditions–250 ms of judgment as well as a slower one? (as you reread the article, look for the part about "cognitive pressure".) What do these conditions suggest about the generalizability and real-world applicability of their findings?

Suggested answers

a.) The independent variable was the degree of makeup that appeared on each target. It had four levels. According to the description in the web story, the independent variable was probably within-subjects–participants viewed all four levels of makeup (none, some, professional, and "glamour"). The dependent variables were the outsiders' ratings of likability, competence, attractiveness, and trustworthiness.

b.) You would probably make a bar graph with "level of makeup" on the x-axis and "rating" on the y-axis. You might have presented all four DV's on the same graph, labeling four different colored bars or lines that represent likability, competence, attractiveness, and trustworthiness.  (To see the actual results of the study, of course, you'd need to look at the original research.)

c.) This study is an experiment–it manipulated the independent variable (makeup level) and measured the dependent variables. Because it was an experiment, the study meets the temporal precedence rule. The results of the study also show covariance–women wearing makeup were judged more favorably. What about internal validity? By using each target as her own control (and only varying how much makeup each was wearing), it helps ensure that makeup use was not confounded with the attractiveness of the women. That shows good internal validity. In addition, the researchers did not let the women in the photos know how much makeup they were wearing, preventing the target women from inadvertently posing more confident facial expressions. Because the experiment appears to be well done (and meets all three causal rules) we can conclude that makeup can cause women to appear more competent. 

d.) The researchers seem to be using the 250ms version of the study as a way of mimicking real-world situations in which people make quick decisions or when they are distracted. The basic pattern of results replicated across two studies (with the exception of the trustworthiness ratings of women in the "glamour" condition), supporting the study's replicability and external validity. In addition, by presenting 25 diverse women as targets in this study, the researchers are able to say that the makeup effect can probably generalize to a variety of female targets.