Psychology research methods

  • Created by: amarag
  • Created on: 28-03-16 23:02


Alternate hypothesis- predicts a difference or correlation

  • There is a difference in the way that Japanese and American people interpret emotions in faces
  • More people will obey orders from someone dressed in a uniform than someone dressed in civilian clothes
  • There is no correlation between the number of crimes a parent commits and the number of crimes their sons commit

Null hypothesis- predicts no pattern or trends

  • There is no difference in the way that Japanese and American people interpret emotions in faces
  • There is no correlation between the number of crimes a parent commits and the number of crimes their sons commit
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Independent variable- CAUSE

  • Whether someone is wearing a uniform or civilian clothes, from Japan or the US, whether word or image is presented

Dependant variable-EFFECT

  • This is the thing they measure
  • Like, how many people obey, measure rating of faces and measure how many words/images are recalled
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Extraneous variables- contextualise to question

Relate to the IV and the DV

  • Customer/employee tiredness
  • Loudness of music
  • Time of day
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Standardisation- contextualise

  • Standardisation refers to keeping variables the same across conditions.
  • Standardised instructions are therefore a set of instructions that remain the same for all participants to avoid some participants being more or less informed than others.
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Repeated measures design- experiemental design

  • The same participants take part in each condition of the independent variable.
  • This means that each condition of the experiment includes the same group of participants
  • For example, test participants in both the conditions of noisy and quiet.
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Independant groups design- experimental designs

  • Each condition will have a different group of participants
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Repeated measures- +ves and -ves


  • Fewer people are needed as they take part in all conditions, therefore more practical
  • Allows the researcher to exclude the effects of individual differences that could occur if two different people were used instead


  • Order effects more likely to occur, this can affect the reliability of the results
  • Eg, ppts may underperform in the second condition because they are tired and bored and not because it is noisy
  • Or, ppts may perform better in second condition because they're getting used to the experiment and improving through practice.
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Independant groups design- +ves and -ves


  • Avoids order effects- since different ppts used in the conditions, they can’t get worse through tiredness or boredom, nor get better through practice


  • More people are needed than with the repeated measures design.
  • Different ppts take part in different conditions. This means that any differences between two conditions could be down to the individual differences of ppts.
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Random sampling- +ves and -ves


  • There is no bias in who is chose, it tends to give a good cross-section of people; a representative sample


  • Because there is no control over who is being selected, an unusual sample may be drawn. Eg, everyone from the one-year group is chosen from the entire school
  • Not very practical, especially when the population is large as it would take time to compile names of all people in a target population and even if they're drawn, they may choose not to partake
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opportunity sampling - +ves and -ves


  • The main advantage of opportunity sampling is that it is an easy way to obtain a large amount of data in a relatively short time frame
  • Also, a very convenient way s it's cheap


  • Tends not to be very representative
  • Eg, people who volunteer themselves for research may be more confident than the average person or may be very good at the task that is being investigated and therefore that's why they want to partake
  • Similarly, if psychologists use people they know, then the people may all have similar characteristics as they may be from a similar social class or limited age range. Therefore, it would not be fair to generalise results to other social classes or age groups.
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Ethical considerations

  • Informed consent
  • Right to withdraw- ppts may not like the method of investigation or are distressed
  • Confidentiality- ppts may not want other people to know as private

Protection of ppts-should not:

  • be deceived
  • be caused unnecessary distress
  • be caused discomfort or embarrassment
  • be caused physical harm or be put at risk of harm
  • Ppts should generally leave a study in the same state as when they entered
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Experiements in general


  • Researcher manipulates an IV
  • Researcher measures a DV
  • Researcher attempts to control all other extraneous variables that may affect the outcome of the experiment

As experiments are set up and controlled by a researcher, the researcher can reliably establish a cause and effect as they have manipulated  the IV and controlled extraneous variables, then they know whether it has an effect on the DV or not

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strengths and weaknesses of a laboratory experimen


  • Has a very high level of control. This is bcs the environment is being controlled as well as many other variables. Makes it easier to establish a cause and effect compared with a field experiment


  • Its findings lack ecological validity. This is because the controlled environment is often artificial.
  • Tend to have more demand characteristics than field experiments. This is because people tend to know that they are taking part in a lab experiment. Also, more things are set up in a lab experiment so there are more clues to what the experiment is about. Outcome of this is that ppts may work out what the experiment is about and change their behaviour accordingly.
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strengths and weaknesses of a field experiment


  • Has a higher ecological validity than a lab experiment. This is because the experiment is carried out in a natural environment. Meaning any findings are more applicable to real life


  • Has less control over variables than lab experiments because the setting is naturally occurring. This makes it harder to establish cause and effect. Uncontrolled variables in the environment may be affecting the DV.
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Features of a questionnaire (type of self report m

Consist of a list of pre-set questions. These questions are the same for everyone who takes part in the questionnaire survey.

Closed questions

  • These are questions that have a set number of responses
  • Often in the form of multiple-choice answers or have options like yes/no, always/often/sometimes/rarely/never or a rating scale

Open questions

Such questions for which the respondent chooses their own answers. These types of questions can often be answered in depth.

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Strengths of a questionnaire

  • Can be used to access people's thoughts and feelings
  • All respondents are asked the same set of questions. This means it is possible to compare answers and look for patterns and trends
  • Compared with other self-report methods, questionnaires are relatively easy to administer to a large sample quickly. For example, they can be posted on a website or given out to a group of people at the same time
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Weaknesses of a questionnaire

  • People may lie or exaggerate as there's often no one there to check their responses
  • Respondents may misunderstand the questions and therefore not give reliable answers, especially is there's no one there to administer them
  • With some closed questions, ppts may not be able to find their answer, so may end up missing out questions or giving inaccurate responses.
  • Do not take individuals into account. By asking everybody the same questions, researchers cannot explore individual responses.
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Features of interviews (type of self report method

Carried out face to face. Psychologist directly asks questions of the interviewee.

Two types of interviews:

Structured interviews: interviews where the questions are pre-determined. Means everyone who is interviewed is asked same set of questions

Unstructured interviews: do not have set questions. Instead interviewer asks questions based on the interviewees' answers. Means that the interview runs more like a conversation

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Strengths of interviews

  • Can be used to access people's thoughts and feelings
  • Compared with most questionnaires, interviews have the advantage that people can double check what questions mean. Interviewer can also clarify interviewees' responses if they're not clear
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Weaknesses of interviews

  • People may lie or exaggerate as there is no way of checking the truth. Since the interviewer is present throughout the interview, interviewees may feel obliged to give socially desirable responses rather than their real responses to questions
  • Rely on people being able to explain their thoughts and feelings. Some people do not have the ability to do this because they cannot express themselves clearly. Also, they may not have good insight into themselves
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Features of observations

  • Overt observation is one in which ppts are aware that they're being observed
  • Covert observation is when ppts are unaware that they're being observed
  • Participant observations, researcher actually participates with the group of people they're studying
  • Non-participant observations, researcher would observe the group from a distance and not interfere with their activities

General weakness of observations

  • Observer bias. This is the idea that researchers see what they want to see and interpret behaviours from their own perspective.
  • Solution to this is to use more than one observer. This should give inter-rate reliability to any findings
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Overt observations- strengths and weaknesses


  • More ethical than covert observations because participants must have given consent to be observed


  • Participants are likely to behave differently from normal if they know they are being watched. Known as observer effect and makes results less valid.
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Covert observations- strengths and weaknesses


  • People will behave more naturally than when they know they are being observed


  • Can be difficult to record data accurately without being discovered. Especially the case if the observation is a ppt observation as well
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Participant observations- strengths and weaknesses


  • Over non-ppt observation is that researchers can actually experience a situation from the ppt's POV, giving more realistic results


  • Researcher can affect the dynamics of the group they join. The group becomes a different group from normal with their additional member
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Non-participant observations- strengths and weakne


  • Researcher can be more objective when standing back from the group being observed. When researchers are too involved with a group they may be too subjective


  • It's easier for a researcher to miss details of an activity when they are separate form it rather than part of it.
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Types of studies

  • Case studies
  • Correlation studies
  • Longitudinal studies
  • Cross-sectional studies
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Case studies

  • Use methods like unstructured interviews and observations
  • May include looking at past records of a person
  • Carried out in a small sample- may be one individual or one group
  • Involves an in-depth analysis of the individual or group under investigation
  • Quite often the individual or group is studied because it is unusual in some way
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Correlation studies

  • Collects data through questionnaires, structured interviews, observations...
  • Involves collecting two sets of data from a sample, and then analysing it to see if there is an association between them
  • Once the researcher has carried out the correlation study, they can see if there is a positive, negative or no correlation.
  • If there's a positive correlation, it means that as one variable increases then so does the other
  • If there is a negative correlation it means that as one variable increases, then the other decreases
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Longitudinal studies

  • The chosen method is conducted over a long period of time, so that the researchers can chart any changes
  • Very useful for studying psychological development
  • Very time consuming and tend to be expensive because of this
  • Also takes a long time to collect the final results- makes it even complicated if the ppts in original sample decide to drop out
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Cross-sectional study

  • Involves comparing two groups of people who represent the different stages of development that the psychologist is interested in
  • However, researcher is not actually comparing the same people. This means that any differences could be due to individual differences
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Types of data

Quantitative data

  • This is numerical data.
  • If a psychologist takes a measurement, they will have quantitative data

Qualitative data

  • This is descriptive data.
  • Means it is normally in the form of words.
  • However, it can be in other formats which offer some detail, like images
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Descriptive data

  • This is data that summarises patterns and trends in quantitative data
  • Rather than presenting the raw data it describes them in more general terms
  • Averages are an example of descriptive data
  • An average gives the researcher a score that represents the data set that it comes from
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Ways of calculating averages

  • MODE
  • MEAN
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Presenting data

Quantitative data can be presented more visually by using techniques like tables, charts and graphs.

  • Table
  • Bar chart
  • Line graph
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  • Researchers often question the validity of findings.
  • This means they are actually asking whether they are true or false

Ecological validity- a type of validity

  • If research has ecological validity it means that findings reflect real-life situations
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Reliability and inter-rater reliability

  • Reliability refers to consistency.
  • Means that if results are inconsistent then they are unreliable

Inter-rater reliability

  • Unreliable results may be due to researchers' different perspectives on what is being studied.
  • This is why it is useful to have more than one researcher involved in a study.
  • They can check they agree on what they are observing, or on what is being measured.
  • If there is agreement, then findings have inter-rater reliability- more than one person agrees that something has happened.
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How you could achieve inter-rater reliability?

If something is reliable it means if it was done again, the same or similar results would be found. In observations it specifically means to make sure all the observers are recording the same thing, so in this investigation all the observers could be trained before the study to make sure they are looking for the same behaviours from the men and women in the gym’

Reliability could be improved by having more than just the one observer, then their recording could be compared to check they are all interpreting the body language in the same way’

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Demand characteristics

  • People can often work out what experiments are testing using demand characteristics
  • Basically, they're cues that give away the aim
  • Eg, if as a ppt you were asked to complete an exam under quiet conditions and then under noisy conditions, you would probably guess the effect of noise is being tested. You may purposely do worse in the noisy condition to help the researcher out (this is responding to demand characteristics and can make results less reliable)
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Observer effect

  • Is a particular problem in observations
  • Occurs when people behave differently because they know they are being watched. Means their behaviour is not natural and so findings are invalid
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Social desirability

  • Particular problem is self-reports (questionnaires, interviews)
  • This is when ppts give answers that they think the researchers want ot hear, rather than give their true answers. This affects the validity of findings

Explain what is meant by social desirability

  • Social desirability is where the participants answering the questionnaire do not give their honest answer, they give the answer they think the researcher wants them to.    (contextualise here) So in this study they could say they are very influenced by superstitions when really they are not
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Gender bias

  • Occurs when one gender is favoured over another. This can happen if findings are based on studying one sex more than another, or if a researcher's perspective on findings is affected by their own gender


  • A female psychologist who assumes who assumes that attachment is stronger between mother and baby rather than father and baby because of her own experiences
  • Early research on obedience was based on samples of men. Later discovered that it didn't represent women well, as they tended to have higher rates of obedience
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Cultural bias

  • Occurs when one culture is favoured over another. This can happen if findings are based on studying one culture or another, or if a researcher's perspective on findings is affected by their own cultural experiences.


  • A lot of early research on NVC was carried in USA. Based on this researcher suggested that some gestures were universal, even though they hadn't studies people in other countries.
  • A psychologist testing depth cues in African cultures using pictures only familiar to Westerners
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Experimenter bias

  • Occurs where one theory is favoured over another
  • Psychologists prefer different explanations- whether it be biological, cognitive, behaviourist...
  • So psychologists will have certain expectations of what causes something to happen and this may affect how they interpret their findings


  • Any experimenter who believes gender is a product nature may overlook evidence that suggests otherwise
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Great resource! Thanks 

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