From the study by Pepperberg (parrot learning):

Mark scheme

Marking points from the official mark scheme (Feb/Mar 2020). The mark or mark type is shown in brackets.

1. Two marks for full result (meaningful comparison)
2. One mark for partial result
3. e.g.
4. Alex's score was 76.7% [99/129] for all trials and 69.7% [69/99] on first-trial-only performances (2)
5. Alex's score for all trials was better than his first-trial-only performance (2)
6. He scored above chance on first-trial-only performance. (1)
7. One mark for identifying an appropriate methodological strength
8. One mark for applying it to Pepperberg
9. e.g.
10. There were examples of Pepperberg using 'blind' techniques to improve validity (1). For example, the trainer who conducted the trials had not trained Alex to learn same/different (1).
11. The procedure was standardised to aid replicability/reliability (1). For example, the choice of objects/Model-Rival Technique was clearly outlined (to help someone replicate) (1).
12. One mark for outlining an appropriate ethical guideline/ethical issue
13. One mark for applying it to Pepperberg
14. e.g.
15. Housing should take into account the social behaviour of species (e.g. caging);
16. Alex was housed alone which might be stressful as parrots are social/might have been too small.
17. Aversive stimuli should be avoided/punishment should be avoided;
18. The parrot had 'no!' yelled at him when he got a question incorrect (and this could be stressful).
19. Alex may have become bored in between/during trials;
20. Keeping Alex isolated in a cage (at times) could be unethical (application) as parrots are a highly social species (ethical issue);