Research Methods Flashcards
define aim
a statement of what the researcher intends to find out in a research study
define hypothesis
a precise testable statement about the relationship between two variables (IV and DV).
define operationalise
ensuring all the variables are measureable.
define independent variable
something that is manipulated by the experimenter
define dependent variable
what the IV affects, what is measured by the experimenter.
define experiment
a research method where the IV is deliberately manipulated to observe the effect on the DV.
define standardised procedure
a set of procedures that are the same for all participants so the study can be repeated e.g. standardised instructions.
define extraneous variables
variables that make it difficult to detect a significant effect, that may affect the DV but are not part of what is being manipulated or measured.
define directional hypothesis
states the direction of the predicted difference between two conditions/groups. (predicts an outcome - 1 tailed). Used when previous research suggests the findings will produce a particular outcome.
define non-directional hypothesis
predicts there is a difference between two conditions/groups but doesn’t state the direction of the difference. (2 tailed)
define null hypothesis
a prediction of what may not happen in the experiment. e.eg there will be no difference in —- and —–.
Hypothesis rules
- must contain variables that are operationalised. (measurable)
- a directional hypothesis is used due to previous research demonstrating precise findings in an area of research.
- a null hypothesis will state ‘there will be no difference’
- if the study describes a ‘relationship’ it will be correlational and so the hypothesis must include the term ‘relationship’ or correlational.
- a directional hypothesis for a correlational study will include the phrase ‘positive/negative relationship’.
define experimental design
procedures used to control the influence of factors such as participant variables in an experiment.
types of experimental design:
repeated measures design
each participant takes part in each condition.
types of experimental design:
independent group design
different participants are in different groups. They are usually randomly allocated.
types of experimental design:
matched participants design
pairs of participants are matched in terms of key variables e.g. age, IQ. One member is allocated to one condition and the other member is allocated to the other condition.
what are the limitations of repeated measures
- order effects: participants may do better on the second task due to practice or worse due to fatigue e.g. boredom/hunger.
- when in the second condition, participants may guess the purpose of the experiment which may purposely affect their behaviour.
How do we deal with the limitations of repeated measures design?
AB or BA
- divide the participants into 2 groups.
- group 1: each participant does condition A then condition B
- group 2: each participant does condition B then condition A.
ABBA:
All participants take part in each condition twice.
Trial 1: Condition A (morning)
Trial 2: Condition B (afternoon)
Trial 3: condition B (afternoon)
Trial 4: condition A (morning).
Independent groups: Limitations
Individual differences: participants in condition 1 may be naturally better at the task e.g. remembering
More participants are required than for a repeated measures design to have the same amount of data.
How do we control individual differences: Independent group design limitations
Randomly allocate participants to conditions that should in theory distribute participants variables equally. This can be done by putting participants’ names in a hat and drawing out names so every other person goes into group 1.
Matched participants design: limitations
- time-consuming and difficult to match participants on key variables.
- it is not possible to control all participants’ variables e.g. in a memory experiment you can match on memory ability but later find that some participants know memory boosting techniques which others didn’t.
Matched pair design: Limitations
How can these limitations be controlled?
- Restrict the number of variables to match to make it easier
- Conduct a pilot study (a small-scale trial run of the study to test the design of the study) to help identify the key variables worth studying.
Strengths of each experimental design
repeated measures: control participants variables, need fewer participants.
independent groups: less time-consuming than matched participants design, doesn’t suffer order effects as participants are in separate conditions.
matched participants: it tries to match variables so equals fewer order effects and more chance of having more varied participants in each group.
What is mundane realism
how the study mirrors the real world. is the research environment realistic to real life experiences.
what is a confounding variable?
a variable that changes the DV rather than the IV affecting it. therefore the results may be meaningless.
what is an extraneous variable?
‘extra variables’ that can have an effect upon the DV, making it more difficult to detect a significant effect.
what is internal validity?
the degree to which an observed effect was due to experimental manipulation rather than the other variables.
does the research measure what it intends to measure?
what is external validity?
the degree to which findings can be generalised.
what is ecological validity?
the ability to generalise a research effect beyond a particular setting.
what is population validity?
the extent to which the findings can be generalised to other groups besides those who took part in the study.
what is historical validity?
the extent to which the findings from one time period can be applied to another. e.g. Asch ’50s.
what are the 4 types of experiments?
laboratory
field
natural
quasi
Lab Experiments
conducted in a special environment
variables are carefully controlled
PPs are aware they are taking part, but unlikely to know the aim of the study.
Lab Experiments
strengths and weaknesses
strengths:
control over variables leads to high internal validity, confident that the IV is affecting the DV.
weaknesses:
low ecological validity due to PPs knowing they are being watched - may show social desirability.
low mundane realism means people don’t behave as they usually do.
Field Experiments
conducted in a natural ‘ordinary’ environment. PPs are usually unaware of their participation in an experiment, so behaviour will be more natural.
Field Experiments
strengths and weaknesses
strengths:
great mundane realism= high external validity
less likely to respond to cues from the experimenter so behaviour is natural
weaknesses:
IV may lack realism so not like everyday occurences.
low internal validity due to difficulty in controlling extraneous and confounding variables.
Natural experiments
this is a naturally occuring event that couldn’t be researched in a laboratory due to practical and ethical reasons. therefore IV occurs naturally but DV may still be tested.
Natural experiments
strengths and weaknesses
strengths:
high ecological validity and mundane realism due to studying the effects of real issues.
limitations:
IV is not directly manipulated, so can’t establish cause and effect.
Internal validity is questioned as PPs aren’t randomly allocated so there could be confounding variables.
Quasi-Experiments
studies that are almost experiments. IV is naturally occurring and the DV is measured in a laboratory. IV is based on differences that naturally occur between people e.g. gender and age.
Quasi-Experiments
strenths and weaknesses
strengths:
allows comparisons to be made between different types of people
often carried out under controlled conditions and so have the same strengths as a laboratory experiment.
weaknesses:
cannot randomly allocate PPs to conditions so may suffer confounding variables.
low internal validity due to PP knowing they are being studied.
low ecological validity as the DV is likely to be an artificial task.
More problems with experiments
the ‘helping hand’ of PPs or the ‘screw you’ effect. PPs can be overly helpful in experiments or purposely spoil them.
Clever Hans
Horse who was asked what 7 x 4 is. The crowd would count out loud, once they got to 28, he would stamp his hooves. The horse could not count, he just responded to subtle unconscious cues from the owner. Hans did what was expected of him due to cues, he acted on demand characteristics.
Indirect investigator effects
the investigator may operationalise variables in a way to favour a particular result or they may not give clear standardised instructions so their instructions to PPs may influence the PP’s behaviour.