Aims, Hypotheses & Variables (AQA A Level Psychology)

A psychologist wanted to test whether listening to music improves running performance.

The psychologist conducted a study using 10 volunteers from a local gym. The psychologist used a repeated measures design. Half of the participants were assigned to condition A (without music) and half to condition B (with music).

All participants were asked to run 400 metres as fast as they could on a treadmill in the psychology department. All participants were given standardised instructions. All participants wore headphones in both conditions. The psychologist recorded their running times in seconds.

The participants returned to the psychology department the following week and repeated the test in the other condition.

Identify one extraneous variable that could have affected the results of this study. Suggest why it would have been important to control this extraneous variable and how it could have been controlled in this study.

The psychologist decided to conduct an experiment to investigate the effect of watching horror films before going to bed. A volunteer sample of 50 university students consented to take part in the experiment. The 50 students were randomly split into two groups.

Group 1 watched a horror film before going to bed each night for the first week then a romantic comedy before going to bed each night for the second week.

Group 2 watched the romantic comedy in the first week and the horror film in the second week.

When the students woke up each morning, each student received a text message that asked if they had had a nightmare during the night. They could respond ‘yes’ or ‘no’.

The psychologist proposed a directional hypothesis.

Write a directional hypothesis for this experiment.

It was recently reported in a newspaper that time spent playing team sports increases happiness levels. A researcher was keen to find out whether this was due to participating in a team activity or due to participating in physical activity, as he could not find any published research on this.

The researcher used a matched-pairs design. He went into the student café and selected the first 20 students he met. Each student was assigned to one of two groups.

Participants in Group A were requested to carry out 3 hours of team sports per week. Participants in Group B were requested to carry out 3 hours of exercise independently in a gym each week. All participants were told not to take part in any other type of exercise for the 4-week duration of the study.

All participants completed a happiness questionnaire at the start and end of the study. The researcher then calculated the improvement in happiness score for each participant

Write a suitable hypothesis for this experiment.

A psychologist reads a review of a meta-analysis confirming the relationship between recreational screen time and academic performance.

The psychologist decided to design an experiment to test the effects of recreational screen time on children’s academic performance.

The psychologist randomly selected four schools from all the primary schools in her county to take part in the experiment involving Year 5 pupils. Three of the four schools agreed to take part. In total, there were 58 pupils whose parents consented for them to participate. The 58 pupils were then randomly allocated to Group A or Group B.

For the two-week period of the experiment, pupils in Group A had no recreational screen time. Pupils in Group B were allowed unrestricted recreational screen time. At the end of the experiment all pupils completed a 45-minute class test, to achieve a test score.

Briefly explain why a directional hypothesis would be most suitable for this experiment.

Write an appropriate hypothesis for this experiment.

A researcher placed an advert in a university psychology department asking for third year students to participate in a sleep experiment.

Each student had a sleep tracker watch to wear at home for the two-week study. Each morning they were asked to open the sleep tracker app to view their sleep quality data on their mobile phones. The students were unaware that the sleep data they could see on their phones had been manipulated by the researcher. Over the two weeks of the study, each student saw that he or she had had poor sleep quality for seven random nights of the experiment and good sleep quality for the remaining nights.

Every morning, after viewing the sleep data, each student completed a questionnaire about the previous night’s sleep. One of the questions asked the students to rate how well rested they felt, on a scale from 1–10, after the previous night’s sleep. Apart from this, students were asked to continue their normal everyday activities.

Write a directional hypothesis the researcher might use for this study.

The researcher believed that the actual number of hours slept by the students could have affected the results of the study.

Suggest one other extraneous variable that could have affected the results of this study. Explain why it would have been important to control this extraneous variable and how it could have been controlled in this study.