IB · PSYCH HL

Psychology HL

Research methods — HL Paper 3

Name: ____________________Date: October 14, 2026

1.
A researcher wants to test whether listening to background music improves concentration during a reading task. They recruit 40 university students and randomly assign 20 to read with instrumental music playing and 20 to read in silence, then measure comprehension scores on the same test. (a) Identify the independent and dependent variables. (b) State the experimental design used. (c) Identify one extraneous variable the researcher should control, and explain how failing to control it could confound the results. (d) State one ethical consideration the researcher should address before running this study.
[6 marks] · no calculator
Marking points
- Identifies the independent variable as the presence or absence of background music.
- Identifies the dependent variable as the comprehension score on the reading test.
- States that this is an independent (between-groups) measures design with random allocation.
- Identifies a valid extraneous variable, such as prior familiarity with the reading topic, room noise level, or time of day.
- Explains that if this variable is not controlled and differs systematically between the two groups, it could produce or mask a difference in comprehension scores wrongly attributed to the music condition.
- States a valid ethical consideration, such as obtaining informed consent or ensuring the right to withdraw, given participants are randomly assigned to a condition they did not choose.
Examiner tip: An extraneous variable only becomes a real threat to validity once you explain how it could differ between groups and thereby explain the result instead of the true independent variable.
2.
Marking analysis: A learner attempts the following task: “A researcher wants to test whether listening to background music improves concentration during a reading task. They recruit 40 university students and randomly assign 20 to read with instrumental music playing and 20 to read in silence, then measure comprehension scores on the same test. (a) Identify the independent and dependent variables. (b) State the experimental design used. (c) Identify one extraneous variable the researcher should control, and explain how failing to control it could confound the results. (d) State one ethical consideration the researcher should address before running this study.” Their response addresses only this point: “Identifies the independent variable as the presence or absence of background music.” Evaluate the response against the complete 6-mark task. Identify what earns credit and state every additional requirement needed for full marks.
[6 marks] · no calculator
Marking points
- Recognises credit for the stated point: Identifies the independent variable as the presence or absence of background music.
- Identifies the missing requirement: Identifies the dependent variable as the comprehension score on the reading test.
- Identifies the missing requirement: States that this is an independent (between-groups) measures design with random allocation.
- Identifies the missing requirement: Identifies a valid extraneous variable, such as prior familiarity with the reading topic, room noise level, or time of day.
- Identifies the missing requirement: Explains that if this variable is not controlled and differs systematically between the two groups, it could produce or mask a difference in comprehension scores wrongly attributed to the music condition.
- Identifies the missing requirement: States a valid ethical consideration, such as obtaining informed consent or ensuring the right to withdraw, given participants are randomly assigned to a condition they did not choose.
Examiner tip: Treat each marking point as a separate requirement. Do not award the same idea twice, and do not infer work the learner did not show.
3.
A psychologist conducts a case study of a single patient with a rare memory disorder following brain injury, using detailed interviews, cognitive testing, and family reports collected over two years. (a) State one strength of the case study method illustrated by this design. (b) State one limitation of the case study method, specifically regarding generalisability. (c) Suggest one way the researcher could improve the credibility of their findings without abandoning the case study approach. (d) Explain why triangulating multiple data sources strengthens this particular study.
[6 marks] · no calculator
Marking points
- States a valid strength, such as the case study allowing rich, in-depth data on a rare condition that could not ethically or practically be studied experimentally.
- States a valid limitation, such as findings from a single individual not being generalisable to others with the same or different conditions.
- Briefly explains why a rare, unique case may not represent the wider population.
- Suggests a valid improvement, such as using standardised cognitive tests alongside the interviews, or having an independent researcher verify the findings.
- Explains that triangulating multiple data sources allows cross-checking, so a pattern appearing consistently across interviews, testing, and family reports is more credible than one from a single source.
- Notes that this reduces the risk that any one data source's bias, such as the patient's own possibly impaired self-report, unduly shapes the overall conclusions.
Examiner tip: Triangulation strengthens a case study by showing convergence across independent sources — always name which specific sources agree, not just that 'multiple methods were used'.
4.
Marking analysis: A learner attempts the following task: “A psychologist conducts a case study of a single patient with a rare memory disorder following brain injury, using detailed interviews, cognitive testing, and family reports collected over two years. (a) State one strength of the case study method illustrated by this design. (b) State one limitation of the case study method, specifically regarding generalisability. (c) Suggest one way the researcher could improve the credibility of their findings without abandoning the case study approach. (d) Explain why triangulating multiple data sources strengthens this particular study.” Their response addresses only this point: “States a valid strength, such as the case study allowing rich, in-depth data on a rare condition that could not ethically or practically be studied experimentally.” Evaluate the response against the complete 6-mark task. Identify what earns credit and state every additional requirement needed for full marks.
[6 marks] · no calculator
Marking points
- Recognises credit for the stated point: States a valid strength, such as the case study allowing rich, in-depth data on a rare condition that could not ethically or practically be studied experimentally.
- Identifies the missing requirement: States a valid limitation, such as findings from a single individual not being generalisable to others with the same or different conditions.
- Identifies the missing requirement: Briefly explains why a rare, unique case may not represent the wider population.
- Identifies the missing requirement: Suggests a valid improvement, such as using standardised cognitive tests alongside the interviews, or having an independent researcher verify the findings.
- Identifies the missing requirement: Explains that triangulating multiple data sources allows cross-checking, so a pattern appearing consistently across interviews, testing, and family reports is more credible than one from a single source.
- Identifies the missing requirement: Notes that this reduces the risk that any one data source's bias, such as the patient's own possibly impaired self-report, unduly shapes the overall conclusions.
Examiner tip: Treat each marking point as a separate requirement. Do not award the same idea twice, and do not infer work the learner did not show.
5.
A researcher finds a positive correlation between the number of hours teenagers spend on social media each day and their reported levels of anxiety. A newspaper headline claims 'Social media causes teen anxiety'. (a) Explain why this correlational finding does not justify the newspaper's causal claim. (b) Suggest one alternative explanation for the correlation, other than social media use causing anxiety.
[3 marks] · no calculator
Marking points
- Explains that a correlation only shows that two variables change together; it does not show which variable, if either, causes the other to change.
- Explains that no variable was manipulated and no random assignment occurred, so the study design itself cannot rule out other explanations for the observed relationship.
- Suggests a valid alternative explanation, such as reverse causality (already-anxious teenagers using social media more, perhaps to seek reassurance or distraction), or a third confounding variable (such as poor sleep) independently increasing both social media use and anxiety.
Examiner tip: Media headlines routinely convert correlational findings into causal claims — this is one of the most common and important critiques to apply to an unseen research stimulus.
6.
Marking analysis: A learner attempts the following task: “A researcher finds a positive correlation between the number of hours teenagers spend on social media each day and their reported levels of anxiety. A newspaper headline claims 'Social media causes teen anxiety'. (a) Explain why this correlational finding does not justify the newspaper's causal claim. (b) Suggest one alternative explanation for the correlation, other than social media use causing anxiety.” Their response addresses only this point: “Explains that a correlation only shows that two variables change together; it does not show which variable, if either, causes the other to change.” Evaluate the response against the complete 3-mark task. Identify what earns credit and state every additional requirement needed for full marks.
[3 marks] · no calculator
Marking points
- Recognises credit for the stated point: Explains that a correlation only shows that two variables change together; it does not show which variable, if either, causes the other to change.
- Identifies the missing requirement: Explains that no variable was manipulated and no random assignment occurred, so the study design itself cannot rule out other explanations for the observed relationship.
- Identifies the missing requirement: Suggests a valid alternative explanation, such as reverse causality (already-anxious teenagers using social media more, perhaps to seek reassurance or distraction), or a third confounding variable (such as poor sleep) independently increasing both social media use and anxiety.
Examiner tip: Treat each marking point as a separate requirement. Do not award the same idea twice, and do not infer work the learner did not show.
7.
A researcher wants to study how children resolve conflicts during free play, so she observes children at a playground from a discreet distance, recording behaviour as it naturally occurs without any intervention. A second, independent researcher separately codes the same recorded behaviour to check agreement between the two sets of observations. (a) Identify the research method used. (b) State one strength of this method, referring to ecological validity. (c) Identify the purpose of having a second researcher independently code the same behaviour.
[3 marks] · no calculator
Marking points
- Identifies naturalistic (non-participant) observation.
- States that because behaviour is observed in its natural setting without researcher interference, the findings are likely to reflect genuine, real-world behaviour more accurately (high ecological validity) than behaviour observed in an artificial lab setting.
- Identifies that the purpose is to establish inter-observer (inter-rater) reliability, checking whether independent observers interpret and code the same behaviour consistently, which supports the objectivity of the coding system.
Examiner tip: High inter-observer reliability (strong agreement between independent coders) is essential evidence that an observation's coding scheme is objective rather than dependent on one researcher's subjective judgement.
8.
Marking analysis: A learner attempts the following task: “A researcher wants to study how children resolve conflicts during free play, so she observes children at a playground from a discreet distance, recording behaviour as it naturally occurs without any intervention. A second, independent researcher separately codes the same recorded behaviour to check agreement between the two sets of observations. (a) Identify the research method used. (b) State one strength of this method, referring to ecological validity. (c) Identify the purpose of having a second researcher independently code the same behaviour.” Their response addresses only this point: “Identifies naturalistic (non-participant) observation.” Evaluate the response against the complete 3-mark task. Identify what earns credit and state every additional requirement needed for full marks.
[3 marks] · no calculator
Marking points
- Recognises credit for the stated point: Identifies naturalistic (non-participant) observation.
- Identifies the missing requirement: States that because behaviour is observed in its natural setting without researcher interference, the findings are likely to reflect genuine, real-world behaviour more accurately (high ecological validity) than behaviour observed in an artificial lab setting.
- Identifies the missing requirement: Identifies that the purpose is to establish inter-observer (inter-rater) reliability, checking whether independent observers interpret and code the same behaviour consistently, which supports the objectivity of the coding system.
Examiner tip: Treat each marking point as a separate requirement. Do not award the same idea twice, and do not infer work the learner did not show.
9.
A researcher interviewing trauma survivors decides to let each conversation flow naturally, asking open-ended follow-up questions based on what each participant says, rather than asking every participant the exact same fixed list of questions in the same order. (a) Identify the type of interview used. (b) Explain one advantage of this approach for this specific sensitive topic. (c) Explain one disadvantage of this approach for comparing responses across participants.
[3 marks] · no calculator
Marking points
- Identifies an unstructured (or semi-structured) interview.
- Explains that flexibility allows the researcher to follow up sensitively on whatever each individual participant chooses to share, which is particularly appropriate for a sensitive, emotionally difficult topic like trauma where a rigid fixed script could feel insensitive or miss important details.
- Explains that because different participants are asked different specific questions in a different order, it becomes harder to directly compare responses across participants or to identify clear, standardised patterns across the whole sample.
Examiner tip: Structured interviews maximise comparability and consistency across participants; unstructured interviews maximise depth and sensitivity to each individual — the choice should match the research priority.
10.
Marking analysis: A learner attempts the following task: “A researcher interviewing trauma survivors decides to let each conversation flow naturally, asking open-ended follow-up questions based on what each participant says, rather than asking every participant the exact same fixed list of questions in the same order. (a) Identify the type of interview used. (b) Explain one advantage of this approach for this specific sensitive topic. (c) Explain one disadvantage of this approach for comparing responses across participants.” Their response addresses only this point: “Identifies an unstructured (or semi-structured) interview.” Evaluate the response against the complete 3-mark task. Identify what earns credit and state every additional requirement needed for full marks.
[3 marks] · no calculator
Marking points
- Recognises credit for the stated point: Identifies an unstructured (or semi-structured) interview.
- Identifies the missing requirement: Explains that flexibility allows the researcher to follow up sensitively on whatever each individual participant chooses to share, which is particularly appropriate for a sensitive, emotionally difficult topic like trauma where a rigid fixed script could feel insensitive or miss important details.
- Identifies the missing requirement: Explains that because different participants are asked different specific questions in a different order, it becomes harder to directly compare responses across participants or to identify clear, standardised patterns across the whole sample.
Examiner tip: Treat each marking point as a separate requirement. Do not award the same idea twice, and do not infer work the learner did not show.
11.
A researcher wants a sample for a study and simply asks whichever students happen to be available and willing in the university cafeteria at lunchtime. (a) Identify this sampling technique. (b) Explain one specific way this technique could bias the resulting sample. (c) Suggest one alternative sampling technique that would better ensure every member of the target population has an equal chance of being selected.
[3 marks] · no calculator
Marking points
- Identifies opportunity (convenience) sampling.
- Explains a specific bias, such as the sample being limited to students who happen to eat in that particular cafeteria at that particular time, which may over-represent certain courses, schedules, or social groups and under-represent others.
- Suggests random sampling, in which every member of the target population is assigned a number and participants are selected using a random method (such as a random number generator), giving each member an equal chance of selection.
Examiner tip: Opportunity sampling is quick and convenient but its main weakness is always a lack of true representativeness — always tie the specific bias to who is more or less likely to be present at that time and place.
12.
Marking analysis: A learner attempts the following task: “A researcher wants a sample for a study and simply asks whichever students happen to be available and willing in the university cafeteria at lunchtime. (a) Identify this sampling technique. (b) Explain one specific way this technique could bias the resulting sample. (c) Suggest one alternative sampling technique that would better ensure every member of the target population has an equal chance of being selected.” Their response addresses only this point: “Identifies opportunity (convenience) sampling.” Evaluate the response against the complete 3-mark task. Identify what earns credit and state every additional requirement needed for full marks.
[3 marks] · no calculator
Marking points
- Recognises credit for the stated point: Identifies opportunity (convenience) sampling.
- Identifies the missing requirement: Explains a specific bias, such as the sample being limited to students who happen to eat in that particular cafeteria at that particular time, which may over-represent certain courses, schedules, or social groups and under-represent others.
- Identifies the missing requirement: Suggests random sampling, in which every member of the target population is assigned a number and participants are selected using a random method (such as a random number generator), giving each member an equal chance of selection.
Examiner tip: Treat each marking point as a separate requirement. Do not award the same idea twice, and do not infer work the learner did not show.
13.
A psychologist develops a new questionnaire to measure a personality trait and gives it to the same group of participants twice, two weeks apart, finding that participants' scores are highly consistent between the two administrations. (a) Identify the specific type of reliability this procedure tests. (b) Explain the difference between reliability and validity, using this questionnaire as an example: what would need to be additionally shown to demonstrate the questionnaire is also valid, not just reliable?
[3 marks] · no calculator
Marking points
- Identifies test-retest reliability.
- Explains that reliability refers to the consistency of a measure (getting the same result repeatedly), while validity refers to whether the measure actually measures what it claims to measure.
- Explains that to show validity, the researcher would additionally need to demonstrate that the questionnaire's scores genuinely correspond to the personality trait itself, for example by showing scores correlate with an independent, already-validated measure of the same trait, or with real-world behaviour that trait should predict.
Examiner tip: A measure can be highly reliable (very consistent) while still being invalid (consistently measuring the wrong thing) — reliability is necessary but not sufficient for validity.
14.
Marking analysis: A learner attempts the following task: “A psychologist develops a new questionnaire to measure a personality trait and gives it to the same group of participants twice, two weeks apart, finding that participants' scores are highly consistent between the two administrations. (a) Identify the specific type of reliability this procedure tests. (b) Explain the difference between reliability and validity, using this questionnaire as an example: what would need to be additionally shown to demonstrate the questionnaire is also valid, not just reliable?” Their response addresses only this point: “Identifies test-retest reliability.” Evaluate the response against the complete 3-mark task. Identify what earns credit and state every additional requirement needed for full marks.
[3 marks] · no calculator
Marking points
- Recognises credit for the stated point: Identifies test-retest reliability.
- Identifies the missing requirement: Explains that reliability refers to the consistency of a measure (getting the same result repeatedly), while validity refers to whether the measure actually measures what it claims to measure.
- Identifies the missing requirement: Explains that to show validity, the researcher would additionally need to demonstrate that the questionnaire's scores genuinely correspond to the personality trait itself, for example by showing scores correlate with an independent, already-validated measure of the same trait, or with real-world behaviour that trait should predict.
Examiner tip: Treat each marking point as a separate requirement. Do not award the same idea twice, and do not infer work the learner did not show.
15.
A laboratory experiment demonstrates a genuine effect of sleep deprivation on reaction time under tightly controlled conditions, but critics argue the artificial laboratory task bears little resemblance to any real-world situation, raising doubts about whether the finding applies outside the lab. (a) Identify the type of validity being questioned by the critics. (b) Distinguish this from construct validity, which asks a different question about the same study.
[3 marks] · no calculator
Marking points
- Identifies ecological validity (how well the findings generalise to real-world settings and behaviours).
- States that construct validity instead asks whether the specific task or measure used in the study genuinely captures the underlying psychological concept it claims to measure (here, whether the lab reaction-time task genuinely captures 'alertness' or 'cognitive impairment' from sleep deprivation).
- Explains that a study can have good construct validity (a well-designed measure of the intended concept) while still having poor ecological validity (an artificial setting that does not resemble real life), since the two questions are genuinely independent of each other.
Examiner tip: Ecological validity asks 'does this generalise to real life?'; construct validity asks 'does this task actually measure the concept it claims to?' — a study can score differently on each.
16.
Marking analysis: A learner attempts the following task: “A laboratory experiment demonstrates a genuine effect of sleep deprivation on reaction time under tightly controlled conditions, but critics argue the artificial laboratory task bears little resemblance to any real-world situation, raising doubts about whether the finding applies outside the lab. (a) Identify the type of validity being questioned by the critics. (b) Distinguish this from construct validity, which asks a different question about the same study.” Their response addresses only this point: “Identifies ecological validity (how well the findings generalise to real-world settings and behaviours).” Evaluate the response against the complete 3-mark task. Identify what earns credit and state every additional requirement needed for full marks.
[3 marks] · no calculator
Marking points
- Recognises credit for the stated point: Identifies ecological validity (how well the findings generalise to real-world settings and behaviours).
- Identifies the missing requirement: States that construct validity instead asks whether the specific task or measure used in the study genuinely captures the underlying psychological concept it claims to measure (here, whether the lab reaction-time task genuinely captures 'alertness' or 'cognitive impairment' from sleep deprivation).
- Identifies the missing requirement: Explains that a study can have good construct validity (a well-designed measure of the intended concept) while still having poor ecological validity (an artificial setting that does not resemble real life), since the two questions are genuinely independent of each other.
Examiner tip: Treat each marking point as a separate requirement. Do not award the same idea twice, and do not infer work the learner did not show.
17.
A researcher conducts in-depth interviews with 15 people about their experience of chronic illness, then reads through all the transcripts repeatedly, labelling recurring ideas (such as 'loss of independence' or 'renegotiating identity') and grouping related labels into broader patterns across participants. (a) Identify this qualitative data analysis method. (b) Explain the general purpose of this method, in terms of what it allows the researcher to produce from unstructured interview data.
[3 marks] · no calculator
Marking points
- Identifies thematic analysis.
- Explains that the process of coding (labelling recurring ideas) followed by grouping codes into broader themes allows the researcher to systematically organise large amounts of rich, unstructured qualitative data.
- Explains that this produces a structured summary of the key patterns of meaning shared across participants, which would otherwise be very difficult to identify from reading each transcript individually.
Examiner tip: Thematic analysis is the standard method for systematically turning large amounts of unstructured qualitative data (like interview transcripts) into a manageable set of meaningful themes.
18.
Marking analysis: A learner attempts the following task: “A researcher conducts in-depth interviews with 15 people about their experience of chronic illness, then reads through all the transcripts repeatedly, labelling recurring ideas (such as 'loss of independence' or 'renegotiating identity') and grouping related labels into broader patterns across participants. (a) Identify this qualitative data analysis method. (b) Explain the general purpose of this method, in terms of what it allows the researcher to produce from unstructured interview data.” Their response addresses only this point: “Identifies thematic analysis.” Evaluate the response against the complete 3-mark task. Identify what earns credit and state every additional requirement needed for full marks.
[3 marks] · no calculator
Marking points
- Recognises credit for the stated point: Identifies thematic analysis.
- Identifies the missing requirement: Explains that the process of coding (labelling recurring ideas) followed by grouping codes into broader themes allows the researcher to systematically organise large amounts of rich, unstructured qualitative data.
- Identifies the missing requirement: Explains that this produces a structured summary of the key patterns of meaning shared across participants, which would otherwise be very difficult to identify from reading each transcript individually.
Examiner tip: Treat each marking point as a separate requirement. Do not award the same idea twice, and do not infer work the learner did not show.
19.
After analysing interview data and identifying key themes, a qualitative researcher returns to the original participants and shows them a summary of her findings, asking whether the identified themes genuinely reflect their own experience. (a) Identify this technique for establishing the credibility of qualitative findings. (b) Explain why this technique is considered valuable specifically for qualitative (rather than quantitative) research.
[3 marks] · no calculator
Marking points
- Identifies member checking (respondent validation).
- Explains that qualitative research aims to authentically represent participants' own subjective meanings and experiences, rather than testing a pre-set hypothesis with numbers, so checking the researcher's interpretation directly against the participants' own view of it is a natural way to assess whether that goal was achieved.
- Explains that if participants confirm the themes ring true to their experience, this strengthens confidence that the researcher's interpretation is credible and not simply an artefact of the researcher's own assumptions.
Examiner tip: Member checking is one of several credibility techniques specific to qualitative research (alongside triangulation and reflexivity) that serve a role similar to reliability/validity checks in quantitative research.
20.
Marking analysis: A learner attempts the following task: “After analysing interview data and identifying key themes, a qualitative researcher returns to the original participants and shows them a summary of her findings, asking whether the identified themes genuinely reflect their own experience. (a) Identify this technique for establishing the credibility of qualitative findings. (b) Explain why this technique is considered valuable specifically for qualitative (rather than quantitative) research.” Their response addresses only this point: “Identifies member checking (respondent validation).” Evaluate the response against the complete 3-mark task. Identify what earns credit and state every additional requirement needed for full marks.
[3 marks] · no calculator
Marking points
- Recognises credit for the stated point: Identifies member checking (respondent validation).
- Identifies the missing requirement: Explains that qualitative research aims to authentically represent participants' own subjective meanings and experiences, rather than testing a pre-set hypothesis with numbers, so checking the researcher's interpretation directly against the participants' own view of it is a natural way to assess whether that goal was achieved.
- Identifies the missing requirement: Explains that if participants confirm the themes ring true to their experience, this strengthens confidence that the researcher's interpretation is credible and not simply an artefact of the researcher's own assumptions.
Examiner tip: Treat each marking point as a separate requirement. Do not award the same idea twice, and do not infer work the learner did not show.
21.
A study on decision-making recruits only 12 highly educated volunteers from a single elite university, all from similar cultural and socioeconomic backgrounds. (a) Explain why generalising this study's findings to 'people in general' would be problematic. (b) Suggest what the researcher would need to change about the sample to improve the population validity of the findings.
[2 marks] · no calculator
Marking points
- Explains that a small, highly homogeneous sample (similar education, culture, and socioeconomic status) may not be representative of the far more diverse general population, so the specific decision-making patterns found may reflect this particular group's characteristics rather than a universal human tendency.
- Suggests that the researcher would need a larger, more demographically diverse sample, drawn from a wider range of educational, cultural, and socioeconomic backgrounds, to more confidently generalise findings to a broader population.
Examiner tip: Population validity depends on how representative the sample is of the wider population the researcher wants to generalise to — a small, unusual, or highly homogeneous sample is always a red flag for this.
22.
Marking analysis: A learner attempts the following task: “A study on decision-making recruits only 12 highly educated volunteers from a single elite university, all from similar cultural and socioeconomic backgrounds. (a) Explain why generalising this study's findings to 'people in general' would be problematic. (b) Suggest what the researcher would need to change about the sample to improve the population validity of the findings.” Their response addresses only this point: “Explains that a small, highly homogeneous sample (similar education, culture, and socioeconomic status) may not be representative of the far more diverse general population, so the specific decision-making patterns found may reflect this particular group's characteristics rather than a universal human tendency.” Evaluate the response against the complete 2-mark task. Identify what earns credit and state every additional requirement needed for full marks.
[2 marks] · no calculator
Marking points
- Recognises credit for the stated point: Explains that a small, highly homogeneous sample (similar education, culture, and socioeconomic status) may not be representative of the far more diverse general population, so the specific decision-making patterns found may reflect this particular group's characteristics rather than a universal human tendency.
- Identifies the missing requirement: Suggests that the researcher would need a larger, more demographically diverse sample, drawn from a wider range of educational, cultural, and socioeconomic backgrounds, to more confidently generalise findings to a broader population.
Examiner tip: Treat each marking point as a separate requirement. Do not award the same idea twice, and do not infer work the learner did not show.
23.
In one study, participants who guessed the true purpose of an experiment changed their natural behaviour to try to help confirm what they believed the researcher wanted to find. In a separate study, an observer who strongly expected to see aggressive behaviour in a group of boys reported more aggressive incidents than a second, independent observer watching the same boys. (a) Name the phenomenon illustrated by the first study. (b) Name the phenomenon illustrated by the second study. (c) State one way researchers commonly try to reduce the phenomenon described in (b).
[3 marks] · no calculator
Marking points
- Names demand characteristics: participants' behaviour changing based on cues about the study's perceived purpose.
- Names observer bias (researcher bias): the observer's expectations influencing what they perceive and record.
- States a valid method to reduce observer bias, such as using a double-blind design where possible, training observers to use a precisely defined and objective coding scheme, or using multiple independent observers and checking inter-observer reliability.
Examiner tip: Demand characteristics come from the participant's own guess about the study; observer/researcher bias comes from the researcher's own expectations — both are threats to internal validity, but from opposite directions.
24.
Marking analysis: A learner attempts the following task: “In one study, participants who guessed the true purpose of an experiment changed their natural behaviour to try to help confirm what they believed the researcher wanted to find. In a separate study, an observer who strongly expected to see aggressive behaviour in a group of boys reported more aggressive incidents than a second, independent observer watching the same boys. (a) Name the phenomenon illustrated by the first study. (b) Name the phenomenon illustrated by the second study. (c) State one way researchers commonly try to reduce the phenomenon described in (b).” Their response addresses only this point: “Names demand characteristics: participants' behaviour changing based on cues about the study's perceived purpose.” Evaluate the response against the complete 3-mark task. Identify what earns credit and state every additional requirement needed for full marks.
[3 marks] · no calculator
Marking points
- Recognises credit for the stated point: Names demand characteristics: participants' behaviour changing based on cues about the study's perceived purpose.
- Identifies the missing requirement: Names observer bias (researcher bias): the observer's expectations influencing what they perceive and record.
- Identifies the missing requirement: States a valid method to reduce observer bias, such as using a double-blind design where possible, training observers to use a precisely defined and objective coding scheme, or using multiple independent observers and checking inter-observer reliability.
Examiner tip: Treat each marking point as a separate requirement. Do not award the same idea twice, and do not infer work the learner did not show.
25.
Before a study can be published in a reputable academic psychology journal, it is typically sent to other independent experts in the same field, who scrutinise the study's methodology, analysis, and conclusions before deciding if it is suitable for publication. (a) Name this quality-control process. (b) Explain its main purpose within the broader scientific process.
[2 marks] · no calculator
Marking points
- Names peer review.
- Explains that its main purpose is to have independent experts check for methodological flaws, unsupported conclusions, or other weaknesses before publication, helping to maintain the overall quality and credibility of published scientific research.
Examiner tip: Peer review does not guarantee a study is flawless, but it acts as an important filter that catches many serious errors before research reaches the wider scientific community and public.
26.
Marking analysis: A learner attempts the following task: “Before a study can be published in a reputable academic psychology journal, it is typically sent to other independent experts in the same field, who scrutinise the study's methodology, analysis, and conclusions before deciding if it is suitable for publication. (a) Name this quality-control process. (b) Explain its main purpose within the broader scientific process.” Their response addresses only this point: “Names peer review.” Evaluate the response against the complete 2-mark task. Identify what earns credit and state every additional requirement needed for full marks.
[2 marks] · no calculator
Marking points
- Recognises credit for the stated point: Names peer review.
- Identifies the missing requirement: Explains that its main purpose is to have independent experts check for methodological flaws, unsupported conclusions, or other weaknesses before publication, helping to maintain the overall quality and credibility of published scientific research.
Examiner tip: Treat each marking point as a separate requirement. Do not award the same idea twice, and do not infer work the learner did not show.
27.
Rather than relying on the results of just one study, a researcher statistically combines the results of 40 separate published studies that all investigated the same research question, to calculate a single, more precise overall estimate of the effect. (a) Name this research technique. (b) Explain one advantage of this technique over relying on any single study. (c) Explain one limitation of this technique, referring to the fact that studies finding a significant effect are more likely to be published than studies finding no effect.
[3 marks] · no calculator
Marking points
- Names a meta-analysis.
- Explains that combining data from many studies gives a much larger overall sample size, increasing statistical power and producing a more reliable, precise estimate of the true effect than any single, smaller study could provide.
- Explains publication bias (the 'file drawer problem'): since studies with significant, positive findings are more likely to be published than studies with null results, a meta-analysis built only from published studies can overestimate the true size of an effect.
Examiner tip: A meta-analysis is only as good as the studies that go into it — publication bias means the published literature itself can be a skewed, non-representative sample of all research actually conducted on a topic.
28.
Marking analysis: A learner attempts the following task: “Rather than relying on the results of just one study, a researcher statistically combines the results of 40 separate published studies that all investigated the same research question, to calculate a single, more precise overall estimate of the effect. (a) Name this research technique. (b) Explain one advantage of this technique over relying on any single study. (c) Explain one limitation of this technique, referring to the fact that studies finding a significant effect are more likely to be published than studies finding no effect.” Their response addresses only this point: “Names a meta-analysis.” Evaluate the response against the complete 3-mark task. Identify what earns credit and state every additional requirement needed for full marks.
[3 marks] · no calculator
Marking points
- Recognises credit for the stated point: Names a meta-analysis.
- Identifies the missing requirement: Explains that combining data from many studies gives a much larger overall sample size, increasing statistical power and producing a more reliable, precise estimate of the true effect than any single, smaller study could provide.
- Identifies the missing requirement: Explains publication bias (the 'file drawer problem'): since studies with significant, positive findings are more likely to be published than studies with null results, a meta-analysis built only from published studies can overestimate the true size of an effect.
Examiner tip: Treat each marking point as a separate requirement. Do not award the same idea twice, and do not infer work the learner did not show.
29.
A researcher proposes a study in which participants are secretly filmed in a public restroom to observe genuine, unselfconscious handwashing behaviour, without being told about the study beforehand or asked for consent, arguing that informing participants would make their behaviour artificial. (a) Identify two specific ethical principles this proposed study would violate. (b) Suggest one way the researcher could study genuine, unselfconscious behaviour of this kind while still meeting modern ethical standards.
[3 marks] · no calculator
Marking points
- Identifies a lack of informed consent, since participants were not told about the study or asked to agree to take part.
- Identifies a violation of privacy, since participants were filmed in a setting (a public restroom) where they would reasonably expect a significant degree of privacy.
- Suggests a valid ethical alternative, such as observing handwashing behaviour only in a setting with a fully reduced expectation of privacy and with prior general notice that observation may occur (without revealing the specific behaviour studied), or debriefing and obtaining retrospective consent immediately afterwards with the right to have their data withdrawn and destroyed.
Examiner tip: A public setting does not automatically mean 'no privacy expected' — a public restroom is a clear example of a place where people retain a strong, reasonable expectation of privacy despite being technically in a public building.
30.
Marking analysis: A learner attempts the following task: “A researcher proposes a study in which participants are secretly filmed in a public restroom to observe genuine, unselfconscious handwashing behaviour, without being told about the study beforehand or asked for consent, arguing that informing participants would make their behaviour artificial. (a) Identify two specific ethical principles this proposed study would violate. (b) Suggest one way the researcher could study genuine, unselfconscious behaviour of this kind while still meeting modern ethical standards.” Their response addresses only this point: “Identifies a lack of informed consent, since participants were not told about the study or asked to agree to take part.” Evaluate the response against the complete 3-mark task. Identify what earns credit and state every additional requirement needed for full marks.
[3 marks] · no calculator
Marking points
- Recognises credit for the stated point: Identifies a lack of informed consent, since participants were not told about the study or asked to agree to take part.
- Identifies the missing requirement: Identifies a violation of privacy, since participants were filmed in a setting (a public restroom) where they would reasonably expect a significant degree of privacy.
- Identifies the missing requirement: Suggests a valid ethical alternative, such as observing handwashing behaviour only in a setting with a fully reduced expectation of privacy and with prior general notice that observation may occur (without revealing the specific behaviour studied), or debriefing and obtaining retrospective consent immediately afterwards with the right to have their data withdrawn and destroyed.
Examiner tip: Treat each marking point as a separate requirement. Do not award the same idea twice, and do not infer work the learner did not show.