Answer:
Staged manipulation
Step-by-step explanation:
Staged manipulation refers to when events are orchestrated in an experiment for positive manipulation of the independent variable, it refers to built events and circumstances which allow manipulation of the independent variable. Easy or complicated. Often, a confederate is involved.
A confederate is someone who seems to be just another participant but is actually a researcher's accomplice.
Ralph has a confederate cut in front of a person who is second or ninth in line at a grocery store checkout counter. He then records the number of verbal responses towards the confederate as a measure of aggression. The manipulation employed in this study is an example of a STAGED manipulation.