Research Methods Flashcards
Independent variable (IV)
- In experiments
- Manipulated by the experimenter in order to observe effects on dependent variable
- E.g. what are the two conditions of the experiment? - male or female
- This is used to establish cause and effect
- The one that is CHANGED
Dependent variable (DV)
- In experiments
- The DV depends in some way and the IV
- How the effect of the change in the IV is measured
- E.g. different scores, different times
- The one that is MEASURED
Co-variables
- In correlations
- When using a correlation, it is impossible to directly manipulate the variables
- In this circumstance we would have to measure two separate variables and then compare them to each other
Operationalisation
Making something measurable
Examples of operationalisation of variables
1 - stating the method of measuring the DV
DV is time = not operationalised
DV is time takes to do task in seconds = operationalised
2 - Using a questionnaire to measure happiness
Extraneous variables
Any variables that might affect the DV so we try to keep them the same to ensure a fair test
Confounding variables
Variables which have not been kept the same (controlled) so may have affected the DV
Experiments
Involve manipulation of an independent variable to measure the effect on a dependent variable. There are 4 types of experiment.
Lab experiment
- IV is directly controlled by the experimenter
- Takes place in tightly controlled, artificial situations
Strengths of lab experiments
- Easy to replicate
- High internal validity due to good control of variables
- Can establish cause and effect
Limitations of lab experiments
- Lacks ecological validity as tasks are more artificial
- Participants may try to guess the aim of the study
An example of a lab experiment
Lotus and Palmer
Field experiment
- IV is deliberately manipulated by the researcher
- A controlled experiment
- It is conducted in a more “ordinary” environment
- The “field” is anywhere outside of the laboratory
Strengths of field experiments
- Participants are usually not aware they are participating in an experiment so behaviour may be more natural as they are not responding to demand characteristics
- Participants may be more relaxed
- Higher external validity due to greater mundane realism
Limitations of field experiments
- Lower internal validity (more difficult to control extraneous and confounding variables)
- Ethical issues as participants may not know they are being studied
Natural experiment
- Conducted when it is not possible, for ethical or practical reasons, to deliberately manipulate and IV
- The IV varies naturally and would vary whether or not the researcher was interested
Strength of natural experiments
- Enables psychologists to study “real” problems such as the effects of a disaster on health (mundane realism and ecological validity)
Limitations of natural experiments
- Cannot demonstrate causal relationships because IV is not directly manipulated
- Random allocation is not possible so confounding variables may impact internal validity
- Can only be used where conditions vary naturally
Quasi experiment
- Studies that are “almost” experiments
- IV is actually not something that varies at all - it is just a condition that exists e.g. age and gender
Strength of quasi experiments
- Allows comparisons between types of people
Limitations of quasi experiments
- Participants may be aware of being studied, creating demand characteristics and reducing internal validity
- Dependent variable may be a fairly artificial task, reducing mundane realism
Example of a field experiment
Bickman (IV - what they were wearing (dressed as a milkman, security guard and ordinary clothes) DV - obedience)
Example of a natural experiment
Effects of institutionalisation in Romanian orphanages
Rutter (IV - age of adoption, DV - IQ)
Example of a quasi experiment
Miller (1956)
How age affects short-term memory (digit span test)
What chart is used for experiments?
Bar chart
Which graph is used for correlations?
Scattergraph
What do correlations not look at?
Whether an IV affects a DV
Correlations
Allow a psychologist to examine the relationship between two co-variables. These co-variables exist and are not manipulated by the psychologist.
Correlation coefficient
Tells us whether a relationship is positive or negative, and tells us how strong the relationship is. It is a number between -1 and +1.
Strengths of correlations
- Psychologists can study a topic where it would be unethical to carry out an experiment
- The strength of a relationship can be found by using scattergraphs and calculating the correlation coefficient
Limitations of correlations
- Can’t establish cause and effect between the co-variables i.e. we can’t say that changing one variable causes the other variable to change
- Another variable may cause both variables to change
Observational study
A study that involves observing actual behaviours
Controlled observation
The setting for the observation is structured and controlled e.g. Ainsworth’s strange situation
Naturalistic observations
- Setting for an observation is natural
- Designed to examine behaviour without the experimenter interfering with it
What might a naturalistic setting do to demand characteristics?
Reduce them as people will act more naturally
Strength of naturalistic observations (will be the opposite for controlled observations)
- People tend to behave more naturally than for controlled observations (providing higher external validity)
- The information gathered tends to be richer and fuller than experimental methods
Limitations of naturalistic observations (will be the opposite for controlled observations)
- Researcher has no control over the situation. Low internal validity and reliability, compared to controlled observations
- Difficult to replicate
Covert observations
Participants’ behaviour is watched and recorded without their knowledge and consent
Overt observations
Participants’ behaviour is watched and recorded with their knowledge and consent
Strength of covert observations (will be the opposite for overt observations)
Should be higher in validity as people may change their behaviour if they are being observed
Limitation of covert observations (will be the opposite for overt observations)
Raise significantly more ethical issues regarding privacy as you shouldn’t observe covertly where people would not expect to be seen
Hawthorne effect
People change their behaviour when they know they are being observed
Participant observations
The researcher observes the participants from within the group that they are observing
Non-participant observations
The researcher observes the group of participants from a location away from the group
Strength of participant observations (will be the opposite for non-participant observations)
They give a greater insight into the behaviour of the group
Limitation of participant observations (will be the opposite for non-participant observations)
They are less likely to be objective
Why might researchers lose objectivity in a participant observation?
Researchers may form relationships with those they are observing
Unstructured observations
The researcher records all relevant behaviour but has no system
Problems with unstructured observations
- There may be too much to record
- The behaviours recorded will often be those which are most visible or eye-catching to the observer but these may not be the most important or relevant behaviours
A situation where an unstructured observation would be used
Where research has not been conducted before as a kind of pilot study to see what behaviours might be recoded using a structured system
Structured observations
- Aim to be objective and rigorous
- A researcher uses various systems to organise observations such as behavioural categories and sampling procedures
- More common in psychology
Behavioural categories
Dividing a target behaviour (e.g. stress) into a subset of specific and operationalised behaviours
Behavioural categories should…
- Be objective (no inferences need to be made about behaviours)
- Cover all possible component behaviours and avoid a “waste basket” category
- Be mutually exclusive (you should not have to mark two categories at one time)
Event sampling
Counting the number of times a certain behaviour (event) occurs in a target individual or individuals e.g. counting how many times a person smiles in a 10 minute time period
Time sampling
Recording behaviours in a given time frame e.g. noting what a target individual is doing every 30 seconds or some other time interval. At that time to observer may tick one or more categories from a checklist
Interviews
- A face-to-face interaction that results in the collection of data
- Questions can be predetermined or created in response to answers
Strengths of interviews
- A lot of data can be collected
- Face-to-face can assess emotions
Limitations of interviews
- Social desirability bias and interview bias
- Requires skilled personnel
Social desirability bias
People want to look good so they may be dishonest
Interviewer bias
The way the interviewer treats the participants might affect their answers
A biased interviewer may ask leading questions or otherwise affect the behaviour of participants, reducing validity
Structured interview
Pre-determined questions i.e. a questionnaire that is delivered face-to-face with no deviation from the original questions
Unstructured interview
New questions are developed as you go along
Strength of a structured interview
Easier to compare people’s answers
Strength of an unstructured interview
More natural so people may reveal more
Recording the interview
- Taking notes may interfered with the interviewer’s listening skills
- Taking notes may also make the respondent feel like they’re being evaluated especially if the interviewer doesn’t write everything down
- Best to record the interview and transcribe later
What effect can having an interviewer who is interested in the respondent’s answers have?
It may increase the amount or the quality of the information
Questionnaire survey
- Data that is collected using a set of written questions
Strengths of questionnaires
- A lot of data collected
- Does not require specialist administrators
- More anonymous
Limitations of questionnaires
- Leading questions and social desirability bias
- Biased samples
Clarity (questionnaires)
The respondent needs to know exactly what is being asked. There should be no ambiguity.
Bias (questionnaires)
The questions should not lead the respondents to a particular answer e.g. social desirability bias
Analysis (questionnaires)
The answers need to be easy to analyse
Open questions
Harder to analyse due to the wide range of answers
Closed questions
Have a limited range of answers e.g. yes or no, scales etc. and are therefore easy to analyse
Filler questions (questionnaires)
Including some irrelevant questions helps distract respondents from the true purpose of the study
Prevent demand characteristics
Sequence for the questions (questionnaires)
It is better to start with easier questions as it puts respondents at ease
Sampling technique (questionnaires)
Questionnaires often use stratified sampling, which makes the answers more representative
Pilot study (questionnaires)
Test the questionnaires on a small group of people so they can be refined later
Case studies
An in depth study that gathers a lot of detail about one person or a small group
Examples of case studies
- Phineas Gage
- HM
- Tan
Why is data triangulated?
To form a consistent conclusion about the case
Strengths of case studies
- Good ecological validity (real life application)
- A more ethical way of studying psychology (can’t inflict pain or trauma so take the opportunity)
Limitations of case studies
- Cannot generalise
- Cannot replicate
- Time consuming/ have to employ people for an extended period of time
Content analysis
- A technique for systematically summarising and describing any form of content-written, spoken or visually
- It converts qualitative data to quantitative data
5 steps for content analysis
- Data is collected
- Researcher reads through or examines the data, making themselves familiar with it
- The researcher identifies coding units
- The data is analysed by applying the coding units
- A tally is made of the number of times that a coding unit appears
Thematic analysis
- The researcher closely examines the data to identify common themes, topics, ideas and patterns of meaning that come up repeatedly
- Psychologists may select quotes from the material they are analysing to exemplify the themes they’ve identified
Strengths of content analysis
- Reliable way to analyse qualitative data as the coding units are not open to interpretation and so are applied in the same way over time and with different researchers
- It is an easy technique to use and is not too time time consuming
- It allows a statistical analysis to be conducted if required as there is usually quantitative data as a result of the procedure
Limitations of content analysis
- Causality cannot be established as it merely describes the data
- As it only describes the data it cannot extract any deeper meaning or explanation for the data patterns arising from
Aim
A statement of what you want to find out e.g. are males or females better drivers?
Hypothesis
A formal prediction of what you think will happen. It must include the operationalised IV and DV e.g. male drivers will have fewer faults on a driving test than female drivers
A directional hypothesis/one tailed
Predicts the kind of difference between two conditions in an experiment or the direction of the correlation
E.g There will be a positive correlation between number of homeworks completed and final grade
When do we use a directional hypothesis?
When there is previous research to support the prediction
A non-directional hypothesis
Simply predicts that there will be a difference or a correlation but doesn’t state what the direction will be e.g. there will be a difference between number of error made by males and females in a driving test
When do we use a non-directional hypothesis?
When there is no previous research or when there are mixed findings
Target population
A group of people that are the focus of the researcher’s interest
Sample
The group who take part in the research. We want the sample to be representative of the target population
Random samples
Everyone in the entire target population has an equal change of being selected
Put names in a hat and draw out without looking
Strengths of random sampling
- It is widely accepted that since each member has the same probability of being selected, there is a reasonable chance of achieving a representative sample
- It is an unbiased method
Limitations of random sampling
- It can be impractical (or not possible) to use a completely random technique e.g. the target group may be too large to assign numbers to
- The people you select may not want to take part
Opportunity sampling
Uses people from target population available at the time a willing to take part. It is based on convenience.