Final answer:
In the study of the "red effect", the independent variable is the color of the shirt, with red and white as the levels, and the manipulation is staged. The attractiveness of the person, which participants rate, is the dependent variable. Random assignment is used to control lurking variables, making the groups comparable.
Step-by-step explanation:
Understanding Independent and Dependent Variables
In the study regarding the "red effect", where attractiveness is rated based on the color of the shirt worn by the person, the independent variable is the color of the shirt. The level of the independent variable, which refers to the various conditions or groups of the independent variable being manipulated, has two levels: red and white shirts. The form of manipulation in this case would be considered staged, as the researcher is controlling the environment and presenting specific conditions to the participants.
Participants are randomly assigned to view a person wearing a specific color of shirt to ensure that other factors do not influence the results, thus limiting potential lurking variables. Random assignment is key to an experimental study as it aims to create comparable groups and isolate the effect of the independent variable on the dependent variable, which in this case is the perceived attractiveness of the person depicted.
It is important to note that the dependent variable is the outcome that is measured in the study, and it is hypothesized to change in response to the manipulation of the independent variable. Therefore, the expectation in this research is that the color of the shirt (independent variable) would have an effect on the attractiveness ratings (dependent variable).