1.Operational Definition: Participants were divided into 3 groups based on whether they said they were often angry, sometimes angry, or rarely angry.
a. Measurement: [Categorical, Continuous]
b. Method: [Observation, Self-Report, Manipulated, Physiological]
2. Operational definition: Reward delay was operationally defined as the amount if time (in seconds from 0 to 10) an experimenter delayed a reward after a pigeon pecks the disk.