Dan is looking for a correlation between the amount children play and how aggressive they are. He is not sure whether children who play more will be more aggressive or will be less aggressive.

Mark scheme

Marking points from the official mark scheme (May/June 2019). The mark or mark type is shown in brackets.

1. [1] 1 mark for a suggested play behaviour or definition with a quantification.
2. How often they participated in a game with other children;
3. How much time they spent playing with other children;
4. The number of times they jumped rope/skipped;
5. Skipping, running, football;
6. Number of times they played = 0
7. Checklist of play behaviours = 0
8. [1] 1 mark for a suggested problem.
9. Play fighting might be hard to tell from real fighting;
10. Children may start to play but end up fighting so hard to break the stream of behaviour;
11. [1] 1 mark for a suggested fighting behaviour or definition with a quantification.
12. How often they punched other children;
13. How much time they spent fighting with other children;
14. The number of times they pinched/bit another child;
15. Behaviours like punching, kicking, pinching, fighting; (at least 2)
16. Number of times they are aggressive = 0
17. Checklist of aggressive behaviours = 0
18. [1] 1 mark for identifying that it is because it is a correlation
19. [1] 1 mark for explanation.
20. It's a correlation so you don't know which (if either of the two) variables are causal factors = 2 marks
21. In a correlation a third factor might be the cause = 2 marks
22. A correlation only allows you to say that two variables are related, not which one is making the other change = 2 marks