Question: Does the black grease beneath football players' eyes really reduce glare or just make them look intimidating? In a variation of a study actually conducted at Yale University, 46 participants placed one of three substances below their eyes: black grease, black antiglare stickers, or petroleum jelly. The researchers assessed eye glare using a contrast chart that gives a value for each participant on a scale measure. Every participant was assessed with each of the three substances, one at a time. Black grease led to a reduction in glare compared with the two other conditions, antiglare stickers, or petroleum jelly (DeBroff & Pahk, 2003).
a. List the independent variable, along with its levels.
b. What is the dependent variable?
c. What kind of ANOVA is this?