A researcher randomly assigns participants to watch one of three kinds of films: one that tends to make people sad, one that tends to make people angry, and one that tends to make people exuberant. The participants are then asked to rate a series of photos of individuals on how honest they appear. The ratings for the sad-film group were 201, 523, and 614; the ratings for the angry-film group were 136, 340, and 301; and the ratings for the exuberant-film group were 838, 911, and 1,007.
(a) Carry out an analysis of variance using the actual scores (use p 6 .01).
(b) Carry out a square-root transformation of the scores (to keep things simple, round off the transformed scores to one decimal place).
(c) Carry out an analysis of variance using the transformed scores.
(d) Explain what you have done and why to someone who is familiar with analysis of variance but not with data transformation.