A researcher interviews 24 adults visiting one public library. In a face-to-face interview, each person is asked how many alcoholic drinks they usually have in a week. The researcher uses the answers to draw conclusions about all adults in the UK.
Explain one way the method of collecting the answers could reduce validity.
Explain one way the sample could reduce validity.
173 exam-style questions on OCR GCSE Psychology 7.3 Analysing Research, covering 7.3.1 Types of Data, 7.3.2 Measures of central tendency, 7.3.3 Other descriptive statistics, 7.3.4 Tables, Charts and Graphs, 7.3.5 Reliability, 7.3.6 Validity and effects on validity, and 7.3.7 Sources of bias. Each one has a worked solution and a mark scheme showing where the marks go.