Explain what is meant by 'reliability', using one example from the study by Bandura et al. (aggression).

Mark scheme

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

1. [2] 1 mark for definition
2. 1 mark for linked example
3. ∞ reliability is about consistency = 1 mark
4. ∞ to be reliable, measures must measure the phenomenon in the same way each time = 1 mark
5. ∞ e.g. Bandura et al. standardised the procedure, e.g. by always having the model display behaviour for the same length of time / in the same place, etc. = 1 mark for example
6. ∞ In Bandura et al., they made sure that both researchers scored aggression in a similar way (= link mark), i.e. were reliable, by using the same list of behaviours (= definition mark) = 2 marks
7. [2] Award 1 mark for identification of problem
8. Award 1 mark for linked example (from any core study except Bandura et al.)
9. ∞ Dement and Kleitman may not have interpreted all the dream reports in the same way = 1 mark
10. ∞ If Schachter and Singer's participants interpreted the scales differently, they could have appeared more happy/angry than other participants = 2 marks
11. Note: These are only examples, there will be many other acceptable answers.