Don and Pinja are planning to test whether older or younger people lose their way more often, even when using a map. They will time how long it takes each participant to find their way between two places in their university, using a map. They are talking about how to find participants and how to start the study. They often see older people returning from the shops in the morning and younger people after school in the evening.

Mark scheme

Marking points from the official mark scheme (May/June 2018). The mark or mark type is shown in brackets.

1. 1 mark for identifying why that aspect of the procedure is important. 1 mark for explanation.
2. so that all participants are working from the same baseline/doing an equally hard task;
3. to standardise the procedure/to improve reliability;
4. so that differences between the participants are due to their navigational ability/are not due to how long it took them to understand the map;
5. 1 mark for identifying why that aspect of the procedure is important (can be generic e.g. 'as a control') 1 mark for explanation.
6. so that the young and old participants have an equal chance of finding their way quickly;
7. as it is more difficult to navigate when there are lots of students at the university;
8. so this would be a control/standardisation/increase reliability;
9. so that differences are not due to the extra time it takes to dodge round people;
10. so the results are more valid;
11. 1 mark for identifying a participant variable. 1 mark for how it would be controlled. × 2
12. How far they normally walk/how fit they are; Select young and old people with similar fitness levels/make the course shorter for the old people;
13. Whether they know the university; make sure all participants do not know the university already/ask them if they have been there before;
14. Whether they have special navigational skills; ask them about their job/hobbies and exclude skilled people/taxi drivers/orienteers;