General Flashcards
what are the 4 types of experimental research methods?
laboratory experiment
field experiment
natural experiment
quasi experiment
what is a laboratory experiment?
an experiment conducted in a laboratory under highly controlled conditions
what is a field experiment?
an experiment conducted in the everyday and natural environment of the participant
the iv is still controlled
what is a natural experiment?
an experiment conducted in the everyday and natural environment of the participant
the iv is not controlled
what is a quasi experiment?
an experiment where the iv cannot be randomly assigned so participants are not randomly assigned either
give 4 advantages of a laboratory experiment
- easy to replicate and repeat in order to get reliable results
- high internal validity as variables can be controlled and monitored very precisely
- dependent variable can be measured accurately
- extraneous variable can be controlled and reduces the likeliness they’ll interfere with results
give 5 disadvantages of a laboratory experiment
- artificial setting of a laboratory may result in unnatural behaviour and demand characteristics that don’t reflect real life behaviour so results may be hard to generalise and not be entirely accurate
- low ecological validity which makes it hard to generalise findings into real life
- experimenter bias may interfere with results, investigator may give clues as to the research aims, etc
- possibly unethical due to deception or lack of informed consent
- can only use small samples, very hard to test across cultures and countries
give 3 advantages of a field experiment
- less likely for demand characteristics to be an issue as participants are less likely to behave a certain way due to natural surroundings - behaviour is more reflective of real life
- high ecological validity and therefore easier to generalise
- can use a much larger sample so results can be more easy to generalise and more representative of the whole population
give 3 disadvantages of a field experiment
- not all variables can be controlled, confounding variables may interfere and ruin results - lower internal validity
- hard to replicate and repeat experiment in the same way to ensure reliability of results
- issues of deception and lack of informed consent especially if they’re unaware they’re being studied
give 4 advantages of a natural experiment
- behaviour is more likely to be reflective of real life so results may be more valid and accurate - high ecological validity
- less likely for demand characteristics to be an issue if participants don’t know they’re being studied
- eliminates experimenter bias as iv is not being controlled
- can be used in situations where it would be unethical to manipulate the iv (for example, if it was anxiety)
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give 3 disadvantages of a natural experiment
- more expensive and time consuming as experimenter doesn’t control the iv, it’s just there
- extraneous and confounding variables have a high chance of interfering with results - low internal validity
- difficult to replicate and repeat to ensure reliability of results
give 3 advantages of a quasi experiment
- more genuine and natural behaviour that’s reflective of real life when put in natural settings
- reduces ethical issues regarding the manipulation of iv as in this case, it’s not able to be randomly assigned
- useful when it’s otherwise unethical or not possible to manipulate iv
give 3 disadvantages to a quasi experiment
- participants are not randomly assigned and this could lead to inequivalent/unrepresentative groups as well as experimenter bias
- not all variables are tightly controlled or carefully monitored - low internal validity
- iv is not manipulated, it simply exists
what is an experiment?
an experiment involves manipulating the iv to see the effect it has on the dv while controlling all other variables
establishes and demonstrates cause and effect relationships
what are the 4 types of variable?
- independent - the variable being controlled and manipulated, affects the DV
- dependent - the variable being measured to see if it’s been affected (the results)
- extraneous - any other variables apart from the IV that might have an effect on the DV and can be controlled
- confounding - variables that can’t or haven’t been controlled and do effect/ruin the results
what does operationalise mean?
how something would be tested, measured or defined accurately
we would test memory by doing some sort of memory test like a word list
give examples of EVs and CVs
EVs = age of participants, time limit for tasks
CVs = weather, mood of participants, etc
what is deception and lack of informed consent?
in order to get natural behaviour, people may not know the full extent of the experiment or know they’re being monitored at all
can therefore not give full informed consent
what makes a true experiment?
must have/be….
no bias
carefully controlled
random allocation
what are research aims?
stated intentions of what questions are planned to be answered
why a study is carried out and what it’s intended to find out
what is a hypothesis?
a formal and unambiguous statement of what is predicted
the prediction of the relationship between two variables
testable statements
what are the 2 types of hypothesis?
NULL HYPOTHESIS = a statement of no difference and no effect, stating that nothing will happen
ALTERNATIVE/EXPERIMENTAL HYPOTHESIS = prediction of the effect of the IV on the DV, stating that there will be an effect
what are the 2 types of alternative/experimental hypotheses?
DIRECTIONAL HYPOTHESIS = predicts that there will be an effect on the DV, also predicts the direction of the effect (how it’ll be affected)
NON DIRECTIONAL HYPOTHESIS = anticipates a difference but not a direction, doesn’t include how the DV will be affected
what may a directional hypothesis be referred to as?
one tailed
what would you use a non directional or directional hypothesis?
because previous research suggested it was the most likely outcome
- non directional = used if no previous research was done or there’s contradictory research
- directional = used if previous research suggests that direction and outcome
what is reliability?
consistency of results
if you repeated the experiment, similar results would be obtained each time
what is validity?
accuracy of study
what are demand characteristics?
a participant guesses the nature of the experiment and what behaviour the experimenter is looking for
they change their behaviour and ruin the validity of the results
what does generalised mean?
results being extended beyond the present study and into real life by assuming existing trends will continue
what are 2 types of validity?
internal validity = how accurately an experiment has been carried out in order to be reliable/accurate
external validity = the extent to which experimental results and findings can be generalised to populations, places and times beyond the present study by assuming existing trends will continue
what are 3 types of external validity?
ecological validity = the extent to which findings and results can be generalised to settings beyond the present study
population validity = the extent to which findings and results can be generalised to other populations as a whole beyond the present study
historical validity = the extent to which findings and results can be generalised over time and to different periods of time beyond the present study
what are 2 ways to assess validity?
FACE VALIDITY
CONCURRENT VALIDITY
what is face validity?
how well the experiment appears to test what it claims to, how suitable the experiment is for the purpose of the experiment
> ask participants to directly rate the experiment validity, suitability and purpose via a questionnaire
> high face validity = purpose is clear to all and the experiment must be suitable for that purpose
what is concurrent validity?
how well the experiment corresponds to existing findings that are already known to have good validity
> compare results to older and similar research with good validity
> high concurrent validity = results for this experiment are very similar to other, older experiment results that are known to be very valid and accurate
how can we improve validity? 4 ways
control as many variables as possible so results aren’t interfered with
conduct experiments in natural settings so behaviour is reflective of real life
use large and representative samples
randomise experiment
what are 2 types of reliability?
external reliability = the extent to which results and findings vary from one use to another
internal validity = the consistency of results and findings across items within a test, consistent within itself
what are 2 ways to assess reliability?
TEST RETEST
INTER RATER/OBSERVER
what is test retest?
testing the same participant twice on the same test over a period of time
similar scores/results would suggest the test has internal reliability
what is inter rater testing?
testing how different observers give constant estimates of the same behaviour
researchers would observe the same behaviour independently and compare data
similar data would suggest high external reliability
how can we improve reliability? 5 ways
increase sample size
control test conditions for precisely
training observers in relevant observation techniques
ensuring behaviour categories are correctly operationalised
assessing reliability of tests through test retest method
what are the 3 types of experimental design?
independent groups
repeated measures
matched pairs
what is an experimental design?
how participants are allocated to different IV conditions/levels in the experiment
what are order effects?
the order that participants do the tasks may affect the results (e.g. practise or tiredness)
what are independent groups?
participants are usually split in half and placed in separate and independent groups
each group is in a different IV condition (e.g. group A does task with tv on, group B does it with no tv)
allocation is done randomly
what are repeated measures?
all participants take part in all of the conditions by repeating the tasks in all of the conditions
e.g. each participant does a task with the TV on and then a few days later they do a similar task with the TV off
what is counterbalancing?
where each condition is either tested first or second in equal amounts
half of the group does task in condition A while the other half does it in condition B and then they swap
ABBA or AB then BA
why do we use counterbalancing?
to overcome order effects
what are matched pairs?
match participants based on key and relevant characteristics which may affect the DV
one member of the pair is randomly allocated to a group while the other is allocated to the other group
each group experiences a different condition
what are 2 advantages of independent groups?
avoids order effects such as practise or fatigue because participants only participate in one condition - they won’t get as tired or bored as if they were doing several conditions
each participant has an equal chance of being assigned any group as it’s done randomly, reduces investigator bias