In Table 5.4 are some of the data obtained in a small experiment run by one of my research methods classes to evaluate the possible effects of food on mood. This was done as a between subjects study; each participant was randomly assigned to group 1 (an all carbohydrate lunch) or group 2 (an all protein lunch). One hour after eating lunch each participant rated his or her moods, with higher scores indicating more agreement with that mood. Select one of the mood outcome variables, enter the data into SPSS, examine a histogram to see if the scores appear to be normally distributed, and conduct an independent samples t test to see if mean moods differed significantly between groups. Write up your results in the form of an APA style Results section, including a statement about effect size. Be certain to state the nature of the relationship between food and mood (i.e. did eating carbohydrates make people more calm or less calm than eating protein)?
Also, as an exercise:
If you wanted to design a better study to assess the possible impact of food on mood, what would you add to this study? What would you change?
Reference for this research problem: Spring, B., Chiodo, J., & Bowen, D. J. (1987). Carbohydrates, tryptophan, and behavior: A methodological review. Psychological Bulletin, 102, 234-256.