For each study description below, identify the most likely population of interest, identify the operational definition of the behavior of interest, and identify the scale of measurement of the dependent variable.
a. College student participants are asked to play a virtual ball-tossing game during which some participants are systematically excluded from the game a short time after they begin. The study tested the effects of social exclusion on the participants’ mood. The researchers then ask the students to complete a mood survey in which they rated their mood on a 1 to 7 scale, with higher numbers indicating a more positive mood.
b. To examine the effect of diet on cognitive abilities, researchers taught rats to navigate a maze to reach a food reward. Half of the rats in the study were fed a special diet high in sugar; the other group of rats was fed the standard rat chow. The rats were then tested in the maze after being fed the assigned diet for two weeks. The amount of time it took the rats to reach the food reward in the maze was measured. Rats on the high-sugar diet took longer to run the maze on average than the normal diet rats.
c. A study was conducted to examine the effects of violence on social behaviors in young children. Five-year-olds were asked to play a superhero video game with mild violence (e.g., punching, throwing, etc.). Two researchers who were not aware of the purpose of the study observed the children’s behavior at recess. The number of social behaviors seen (e.g., helping another child, playing cooperatively with another child, etc.) was recorded on a school day both before and after they played the video game.