Dr. Aris and Dr. Novak wanted to investigate the relationship between daily screen time and sleep quality in young adults. They posted an advertisement on a university student union online forum, asking for volunteers aged 18 to 22 to participate in a survey. A total of 80 students responded to the post and completed the online questionnaire.
Table 1 shows the number of participants classified by their screen time (High or Low) and their sleep quality (Good or Poor).
| High Screen Time | Low Screen Time | |
|---|---|---|
| Good Sleep Quality | 18 | 32 |
| Poor Sleep Quality | 22 | 8 |
Table 1
Identify the sampling method used by Dr. Aris and Dr. Novak in their study.
638 exam-style questions on Edexcel A Level Psychology Methods. Each one has a worked solution and a mark scheme showing where the marks go.