Researchers work with a supermarket to place one of two notices beside a trolley-return bay. One notice says that most shoppers return their trolley; the other asks shoppers to return it. On alternating afternoons, a hidden camera records whether each shopper returns a trolley. Vehicle number plates are visible in some recordings. A notice at the car-park exit tells shoppers about the study and gives them a way to have their recording deleted.
Evaluate the use of a field experiment in this study.
139 exam-style questions on OCR GCSE Psychology 7.2 Doing Research, covering 7.2.1 Experiments, 7.2.2 Interviews, 7.2.3 Questionnaires (Surveys), 7.2.4 Observations, 7.2.5 Case Studies, and 7.2.6 Correlations. Each one has a worked solution and a mark scheme showing where the marks go.