Controlling of variables: past paper questions
Real questions on controlling of variables
The newest 20 of 79 written questions. Open one to see it on the real paper.
- 9990/23 · October/November 2025 · Q1b[1]
Outline one reason why counterbalancing is important in experiments.
See it on the paper → - 9990/22 · May/June 2025 · Q7a(ii)[2]
Suggest how Inma could limit the effect of the participant variable.
See it on the paper → - 9990/22 · May/June 2025 · Q7b(ii)[2]
Suggest how Inma could limit the effect of the situational variable.
See it on the paper → - 9990/22 · February/March 2025 · Q7a(i)[2]
Suggest two situational variables that should be controlled so that they are the same for the two sections of the factory.
See it on the paper → - 9990/22 · February/March 2025 · Q7a(ii)[4]
For each of your suggestions in part (a)(i): Explain why each situational variable would be relevant to Jacinda’s study.
See it on the paper → - 9990/21 · October/November 2024 · Q6a(ii)[2]
Dr Eynon needs to control many features about the scenes to ensure that they are similar, in addition to manipulating whether they contain people or not. Suggest two features that Dr Eynon should control about the scenes.
See it on the paper → - 9990/21 · October/November 2024 · Q6a(iii)[2]
Explain why one of the features you have suggested in part (a)(ii) would be important in Dr Eynon’s study. Feature 1 or 2:
See it on the paper → - 9990/22 · October/November 2024 · Q4b(ii)[2]
Explain one strength of a repeated measures design, other than the use of counterbalancing.
See it on the paper → - 9990/22 · October/November 2024 · Q6b(ii)[2]
Explain why the two combinations that you stated in part (b)(i) would be useful.
See it on the paper → - 9990/41 · October/November 2024 · Q12c(ii)[2]
Explain one weakness with your choice of type of experiment.
See it on the paper → - 9990/42 · October/November 2024 · Q12c(i)[2]
Explain one reason for your choice of controls.
See it on the paper → - 9990/42 · October/November 2024 · Q12c(ii)[2]
Explain one weakness of your choice of controls.
See it on the paper → - 9990/21 · May/June 2024 · Q8c[3]
All the pictures and shapes are brightly coloured. Explain one reason why this is important.
See it on the paper → - 9990/21 · May/June 2024 · Q9c(i)[2]
Suggest how Heng could limit the problem of one of these uncontrolled variables.
See it on the paper → - 9990/21 · May/June 2024 · Q9c(ii)[2]
Trying to limit a problem in a study can create further issues. Suggest one issue that your answer to part (c)(i) could create for Heng. Section B Answer all questions.
See it on the paper → - 9990/22 · May/June 2024 · Q9c[2]
Explain one reason why it is important that Carol visits the sports centre at different times of day. , Section B Answer all questions.
See it on the paper → - 9990/33 · May/June 2024 · Q15a(i)[2]
Explain the type of human error made by Joseph.
See it on the paper → - 9990/33 · May/June 2024 · Q15a(ii)[2]
Suggest one way the management at this car factory could avoid this type of human error.
See it on the paper → - 9990/33 · May/June 2024 · Q15b[2]
For the way you suggested in part (a)(ii): Explain one weakness of this way to avoid this type of human error.
See it on the paper → - 9990/22 · February/March 2024 · Q6[6]
Describe practice effects and fatigue effects, using any example(s).
See it on the paper →
What examiners said
This two-mark question, based on a novel scenario, asked candidates to suggest two situational variables that should be controlled so that they are the same for the two sections of the factory. To achieve the two marks on this question candidate responses needed to give two unique situational variables which could include: temperature, light, noise levels, type of work/job, how physical the job wa...
— Examiner report, February/March 2025, 9990/22 Q7(a)(i) (Cambridge)
This four- mark question asked candidates to explain for each of their suggestions in part (a)(i), why each situational variable would be relevant to Jacinda’s study. For each of their variables candidate responses needed: • Explanation of why it is relevant to the study • And then provide further elaboration on this. Inevitably, whether candidates achieved the marks on this question was largely...
— Examiner report, February/March 2025, 9990/22 Q7(a)(ii) (Cambridge)
Many candidates did quite well on this question part, although some incorrectly suggested same number of questions, which was repetition. Some candidates focused on the Dement and Kleitman study rather than the information in the question, which led them to suggest ideas such as making people sleep in a dark room or using a doorbell to wake them up.
— Examiner report, October/November 2023, 9990/21 Q7(a) (Cambridge)
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