"In an attempt to determine which method would assure the bestclass attendance, an educational psychologist had one teacherreward students for attending class with extra points, a secondteacher punish absences by deducting points, a third teacher scoldstudents for absences, and a fourth teacher do nothing unusual.Attendance was best in the first class where the teacher rewardedthe students." This is an example of experimental study. Set up theexperiment (recruiting participants, assignment into groups, whatyou would do and identify the independent and dependent variablesthat are used.