In a memory experiment, one group is tested at 09:00 and the other group is tested at 16:00.
Explain how time of day could affect the validity of this experiment and how it should be controlled.
64 exam-style questions on Edexcel GCSE Psychology 11.1 Designing psychological research, covering 11.1.1 Identify variables, 11.1.2 Controlling extraneous variables, 11.1.3 Write a null hypothesis, 11.1.4 Write an alternative hypothesis, 11.1.5 Methods of sampling, 11.1.6 Experimental and research designs, 11.1.7 Reliability and validity, 11.1.8 Ethical issues in research, 11.1.9 Laboratory experiment, 11.1.10 Field experiment, 11.1.11 Natural experiment, 11.1.12 Interview, 11.1.13 Questionnaire, 11.1.14 Correlation, 11.1.15 Case study, and 11.1.16 Observation. Each one has a worked solution and a mark scheme showing where the marks go.