Following unexpected regional electricity supply problems, a distribution centre temporarily changes the start of its morning shift from 08:00 to 06:00 for one week. The researchers did not request this change. The same employees rate their fatigue from 1 (not at all fatigued) to 10 (extremely fatigued) at the end of the week before the change and at the end of the week with the earlier start.
| Period | Mean fatigue rating | Mean overtime per employee |
|---|---|---|
| Week with 08:00 start | 3.4 out of 10 | 1.2 hours |
| Week with 06:00 start | 6.2 out of 10 | 5.1 hours |
The researchers conclude that bringing the start of the shift forward caused employees' fatigue to increase. Explain whether this conclusion is justified. Use both columns of results in your answer. Identify the type of experiment and explain one reason why this type was suitable for this investigation.
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.