A psychologist investigates the effect of background music on the speed at which students complete a set of maths problems. She tests students individually in a quiet laboratory room at the university and manipulates the type of music played while they work.

Which type of experiment is this?

A Field experiment
B Natural experiment
C Laboratory experiment
D Quasi-experiment

[1 mark]

A researcher carries out a quasi-experiment.

Which two of the following statements are TRUE of quasi-experiments?

Shade two boxes only.

A The independent variable is naturally occurring.
B Participants can be randomly allocated to conditions.
C They always take place in artificial settings.
D They often have reduced internal validity compared with laboratory experiments.
E They always use matched pairs designs.

[2 marks]

A psychologist records whether each shopper in a supermarket donates a coin to charity (yes/no).

Which level of measurement is being used?

A Nominal
B Ordinal
C Interval
D Ratio

[1 mark]

Which one of the following is an example of a directional hypothesis?

A There will be a relationship between age and social-media use.
B Stress will affect performance on a memory task.
C Participants who listen to music will recall more words than participants who work in silence.
D There will be a difference in happiness scores between people who own pets and people who do not own pets.

[1 mark]

A psychologist calculates a correlation coefficient of –0.62 between scores on a shyness scale and number of friends reported.

Which two of the following statements about this result are TRUE?

Shade two boxes only.

A It shows a positive correlation.
B It shows a strong negative correlation.
C As shyness increases, number of friends tends to decrease.
D The correlation proves that shyness causes people to have fewer friends.
E The coefficient must be between –1.00 and +1.00.

[2 marks]

A set of memory scores contains one very high outlier.

Which measure of central tendency is most affected by this outlier?

A Mean
B Median
C Mode
D Range

[1 mark]

A psychologist studies the relationship between time spent revising (in hours) and exam score (percentage).

Which graphical display would be most appropriate to show this relationship?

A Bar chart
B Histogram
C Scattergram
D Pie chart

[1 mark]

A researcher wants a sample that reflects the age and gender proportions of the target population.

Which two of the following are advantages of using a stratified sampling technique?

Shade two boxes only.

A It is the quickest sampling method.
B It can produce a sample that is more representative of the target population.
C It avoids researcher bias in choosing participants.
D It always gives everyone an equal chance of being chosen.
E It guarantees that the sample is random.

[2 marks]

A psychologist collects ordinal stress ratings from the same participants before and after a mindfulness course.

Which inferential statistical test would be most appropriate?

A Mann–Whitney U test
B Wilcoxon signed-rank test
C Chi-squared test
D Unrelated t-test

[1 mark]

Which statement about Type I and Type II errors is correct?

A A Type I error occurs when a true null hypothesis is accepted.
B A Type I error occurs when a true null hypothesis is rejected.
C A Type II error occurs when a false null hypothesis is rejected.
D A Type II error occurs when a false null hypothesis is accepted.

[1 mark]