Dr. Swanson is using a Correlational design. Correlational designs are actively employed in forensic psychology research to establish the relationships between many sorts of factors that are meaningful.
Correlational designs are non-experimental which means that none of the variables are manipulated or under the experimenter's control.
When it is important to investigate whether there is a relationship between specific elements and people's behavior, researchers often pick the correlational design. However, this design is inappropriate to identify the causes of this association.
Therefore, Dr Swanson in order to study the relation between mood and willingness to help a stranger, he is using a correlational design to establish the results. The result can be positive, negative or neutral based on positive, negative and no correlation between the variables respectively.
You can learn more about correlational research design using the following link:
brainly.com/question/13310731
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