Research was carried out into whether students who smile more at their teachers are predicted higher grades than those who smile less. The smiling behaviour of students was rated by a teaching assistant who was present during three lessons. The ratings were then compared to the students’ predicted grades.
(d) Identify and explain how one confounding variable could have affected a student’s smile behaviour rating.
[2]
A student might have been in a bad mood that day because they have had an argument with their friend. This is a confounding variable as it only affects this one particular student.
Type your answer here:
A student might have been in a bad mood that day because they have had an argument with their friend, which means that their smile behaviour rating will be lower than usual as they might smile less when they are in a bad mood. This is a confounding variable as it only affects this one particular student.