Four investigations examine whether primary-school children prefer solving problems alone or in groups. Each psychologist claims that the findings can be applied to all primary-school children in the UK.
| Investigation | Sample and procedure |
|---|---|
| V | 600 pupils from 40 primary schools across England, Scotland, Wales and Northern Ireland each solve an unfamiliar abstract puzzle at a desk in a university laboratory. |
| W | A random sample of 480 pupils drawn from school registers across the UK are given easier puzzles in the group condition than in the individual condition. |
| X | Children from urban and rural schools in every UK region are judged by how many puzzles they complete, not by which setting they say they prefer. |
| Y | The 24 members of one selective junior chess club solve the same puzzles alone and then in groups during their usual weekly meeting. |
Which investigation has the clearest threat to population validity?
Investigation V
Investigation Y
Investigation X
Investigation W
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.