A psychologist showed participants 100 different cards, one at a time.
Each card had two unrelated words printed on it, eg DOG, HAT.
Participants in one group were instructed to form a mental image to link the words.
Participants in the other group were instructed simply to memorise the words.
After all the word pairs had been presented, each participant was shown a card with
the first word of each pair printed on it. Participants were asked to recall the second word.
The following results were found.
Number of words correctly recalled
Mental Image Group
(a) What is the independent variable (IV) in this study?
Some psychology students read about an experiment which suggested that organisation is a useful strategy for improving memory. The students carried out an experiment to investigate the effects of organisation on word recall. They made up a list of 50 items that could be bought in a supermarket. The participants were teachers at their school. One group of participants saw the words organised into categories such as fruit, vegetables, dairy products and cleaning materials. The other group saw the same words presented randomly.
The results are given in the Table below.
The number of words correctly recalled by participants who saw the organised list and participants who saw the random list
Measure of central tendency
Measure of dispersion
(a) Identify a suitable measure of central tendency that could be used with these data.
A researcher carried out an experiment to investigate how many numbers could be held in short-term memory. The participants were 15 children and 15 adults. Participants were asked to repeat lists of random numbers, in the correct order, as soon as they were read out by the researcher. For example, when the researcher said, “3, 4, 2, 8” the participant immediately repeated “3, 4, 2, 8”. When the researcher then said,“7, 5, 9, 6, 4” the participant immediately repeated “7, 5, 9, 6, 4”. One number was added to the list each time until participants were unable to recall the list correctly.Each participant’s maximum digit span was recorded.
(a) Write an appropriate non-directional hypothesis for this experiment.
Psychologists carried out a laboratory experiment to investigate the effectiveness of cognitive interviews. All participants watched the same film of a robbery. They were randomly allocated to Group One or Group Two. Participants were then asked to recall the robbery. The investigators used a cognitive interview to access recall of participants in Group One and a standard interview to access recall of participants in Group Two.
The results of this experiment are summarised in the Figure below.
Average number of correct and incorrect statements made by participants under two different interview conditions
(a) What experimental design was used in this experiment?
It is thought that colours might affect our performance when carrying out certain tasks. Research in this area has been inconclusive. Some studies have shown that red improves performance but others have found the opposite. It could be that these contradictory results have arisen because red is beneficial only for certain kinds of mental processing. Some psychologists tested this hypothesis in a series of independent-groups design experiments using students at a Canadian university.
The experiments involved computer tasks, with either a red, blue or neutral background appearing on the monitor. The researchers found that participants were better at a word-recall task and a spell-checking task when the screen background was red rather than blue or neutral. However, participants thought of more creative ideas when the screen was blue rather than red or neutral.
The researchers concluded that red is beneficial for tasks that require attention to detail whereas blue aids creativity.
(a) What were the researchers’ aims in this study?
Imagine that you are writing up the report for this series of experiments.
(b) What is the purpose of the introduction section of a report?
A psychological report also contains a discussion section. Researchers are
expected to consider their findings critically and discuss issues such as validity.
(c) What is meant by validity?
(d) In the discussion section, researchers are also expected to consider any possible applications of their research. Suggest one practical application that might arise from these findings.
In a further experiment, participants were given 20 blue shapes or 20 red shapes. They were then asked to pick 5 shapes and use them to make a toy suitable for a child aged between five and eleven years. They were given a limited time to carry out this task.
Participants given red shapes made toys that independent judges rated to be more practical but less original, whereas participants given blue shapes made more creative toys.
(e) Explain why the researchers asked independent judges to rate the toys.
(f) Write a set of standardised instructions that would be suitable to read out to
participants in this experiment.
(Total 14 marks)
A psychologist carried out an experiment using an independent groups design. The psychologist wished to investigate the effectiveness of a strategy for memory improvement. In one condition, participants were taught a memory improvement strategy. In the other condition, participants were not taught this memory improvement strategy. All participants were asked to memorise 10 pictures of familiar objects. For example, the first was a doll, the second was an apple. All participants were then given 50 pictures each, and asked to select the original 10.
The psychologist did a pilot study before carrying out the experiment. The results of the experiment are shown in the table below.
(a) Write a directional hypothesis for this experiment.
A researcher wanted to investigate the effectiveness of a language therapy for children with autism. Before the therapy started, the mothers of 10 children with autism each rated the verbal interaction of their child. They used a rating scale of 1–10, where 1 meant very poor verbal interaction and 10 meant very good verbal interaction. Each child then attended a programme of language therapy. At the end of the programme, each mother rated her child again, using the same verbal interaction scale. The scores for each child before and after therapy were used to calculate a median verbal interaction rating.
The data are shown in the table below.
Median ratings of children’s verbal interaction before and after therapy
Median rating of verbal interaction
(a) Name and outline the experimental design used in this study.
(b) Explain one advantage of this experimental design.
(c) Explain what the median ratings in the table above indicate about the effectiveness of the language therapy.
(Total 6 marks)
A researcher wanted to investigate the effectiveness of therapy as a treatment for obsessive-compulsive disorder in children. Before the therapy started, the mothers of 10 children with obsessive-compulsive disorder each rated the anxiety of their child. They used a rating scale of 1–10, where 1 meant not at all anxious and 10 meant extremely anxious. Each child then attended a programme of therapy. At the end of the programme, each mother rated her child again, using the same anxiety scale. The scores for each child before and after therapy were used to calculate a median anxiety rating.
The data are shown in the table below.
Median ratings of children’s anxiety before and after therapy
Median rating of anxiety
(a) Identify two symptoms of obsessive-compulsive disorder.
(b) Name and outline the experimental design used in this study.
(c) Explain one advantage of this experimental design.
(Total 6 marks)
A psychologist wanted to investigate whether or not the presence of an audience had an effect on the performance of a task.
The task was to shoot netballs through a hoop. Each participant took 20 shots.
The experiment took place in a school sports hall.
The psychologist obtained the sample of participants from a local secondary school for girls. She drew the names of 40 participants at random from a list of girls who all played netball regularly. The first 20 participants drawn took part in the experimental condition and the next 20 participants took part in the control condition.
In the experimental condition, each participant took 20 shots. In this condition, 50 pupils from the school acted as an audience watching the performance.
In the control condition, the other 20 participants performed the same task, but this time without the audience watching.
The psychologist observed each girl’s performance and recorded the number of netballs successfully shot through the hoop.
(a) State an appropriate hypothesis for this study.
Research has shown that music can affect the ability to concentrate. Design an experiment that could be carried out in a classroom to test the effects of two different kinds of music on a task requiring concentration (eg word search).
You must use a repeated measures design.
In your answer you should:
• fully operationalise the independent and dependent variables
• provide details of how you would control extraneous variables
• describe the procedure that you would use. You should provide sufficient detail for the study to be carried out.
(Total 10 marks)
The psychologists then wanted to see whether the use of diagrams in medical consultations would affect recall of medical information.
In a laboratory experiment involving a medical consultation role-play, participants were randomly allocated to one of two conditions. In Condition A, a doctor used diagrams to present to each participant a series of facts about high blood pressure. In Condition B, the same doctor presented the same series of facts about high blood pressure to each participant but without the use of diagrams.
At the end of the consultation, participants were tested on their recall of facts about high blood pressure. Each participant was given a score out of ten for the number of facts recalled.
(a) In this case, the psychologists decided to use a laboratory experiment rather than a field experiment. Discuss advantages of carrying out this experiment in a laboratory.
(b) Identify an appropriate statistical test that the psychologists could use to analyse the data from the follow-up study. Give one reason why this test is appropriate.
(Total 6 marks)
A researcher carried out an experiment to investigate misleading information. Participants were shown a photograph in which a man and a woman were talking. The photograph was then taken away and the participants were asked questions about it. Participants were randomly allocated to condition one or condition two.
Participants in condition one were asked:
Question A “How old was the youth in the photograph?”
Participants in condition two were asked:
Question B “How old was the man in the photograph?”
(a) Why is Question A an example of misleading information?
A psychologist studying the primacy effect in impression formation conducted the following experiment.
Each participant was taken to the same room where they listened to a description of a person called ’Alex’. The participants were randomly allocated to one of two groups in the experiment. The psychologist gave each participant the same information about ’Alex’, but the order of the information varied depending on the group.
Five positive points about Alex’s personality were followed by five negative points.
Five negative points about Alex’s personality were followed by five positive points.
After listening to the passage, each participant was asked to state whether they thought ’Alex’ was a friendly person or not. The psychologist recorded how many participants in each group stated that Alex was ’friendly’.
(a) Identify the type of experiment that was conducted. Select one option from the list below.