RESEARCH METHODS (1/3) Flashcards
internal validity
whether results are due to manipulation of IV and not another factor
control over extraneous variables
investigator effects
experimenter unconsciously conveys to participants how they should behave
experimenter bias
demand characteristics
cues which convey to participant the purpose of the study
participants guess the aims of the research and adjust behaviour accordingly
changes results if participants change behaviour to conform to expectations
cause and effect
change in IV is causing a change in DV
external validity
can results be generalised?
is task realistic?
does it have mundane realism?
ecological validity
participants should elicit natural behaviour as if were in real-life setting
environment is important - natural or artificial
refers to whether results can be generalised to other real-life settings
population validity
refers to whether we can extrapolate findings of research to population as a whole
sex, socioeconomic status, occupation, religious belief, background, age, culture
temporal validity
whether findings and conclusions are relevant today
attitudes can change over time e.g. homosexuality was once defined as a mental illness
political context at time of research can impact findings
participant variables
characteristics of individual that may influence outcome of a study (age, intelligence, personality type, gender, socio-economic status)
situational variables
characteristics of environment that might influence outcome of a study (distractions, atmospherics)
researcher variables
variation in characteristics of researcher conducting experiment (gender, mood, sociability)
research methods
strategies, processes and techniques
collect data or evidence
uncover new information, better understand
variables
anything that can be vary or be manipulated
independent = manipulated
dependent = measured
operationalisation
express variables in a form that can be measured
contains units
variables must be operationalised
control of variables
only achieved when all variables are constant
control group provides a baseline measure
extraneous variables
may affect results and dependent variable if not controlled
participant, situational, experimenter bias
single blind procedure
participants don’t know whether they are part of the experiment or control group
double blind procedure
neither participants or researcher knows whether in experiment or control group to avoid unconscious bias
confounding variables
any unmeasured variable that influences the dependent variable
if results are confounded, it is hard to draw causal conclusions
reliability
consistency
validity
accuracy
lab experiments
in a lab
IV directly manipulated
effect on DV measured
EVs controlled as much as possible
standardised procedure
randomly allocate participants
lab experiment strengths
isolation of IV on DV - cause and effect established
strict controls and procedures - easily replicated, check reliability
specialist equipment in research facility
lab experiment weaknesses
artificial - not natural behaviour, reduced ecological validity
likely demand characteristics - adjust behaviour
can’t use when inappropriate to manipulate IV (impractical/unethical)
field experiments
same as lab but in real-life setting
field experiments strengths
high ecological validity - generalise findings to other settings
demand characteristics reduced - unaware of experiment, acts more naturally
field experiments weaknesses
control reduced - more EVs - cause and effect not as easily established, reduces validity
unaware of taking part - could become distressed, difficult to inform, unethical
population validity reduced - on control over participants, may be biased
quasi experiments
similar to lab (similar strengths and weaknesses)
high degree of control over EVs
unable to freely manipulate IV
unable to randomly allocate participants (bias + confound results)
natural experiments
no manipulation or control of any variable
naturally occurring variables
practical and ethical reasons - only method
natural experiments strengths
investigate impractical or unethical situations with any other method
ecological validity is high - study ‘real’ problems
demand characteristics reduced - unaware, act naturally
natural experiments weaknesses
no random allocation of participants (bias + confound results)
no control over environment - reduce validity
ethical guidelines - informed consent, confidentiality, right to withdraw breached
natural events are rare - impossible to replicate for reliability
aims
identifies purpose of investigation
straightforward expression of what the researcher is trying to find out
hypotheses
operationalised hypotheses is a precise, testable statement about the expected outcome of a piece of research i.e. prediction about a difference
researcher would write a directional / non-directional and a null hypotheses
directional hypotheses
when researcher has good idea about what will happen
predict specific outcome about direction of differences
e.g. participants will give more electric shocks to a stranger after playing an anti-social computer game than after playing a non-aggressive game
non-directional hypotheses
when researcher is less sure about what is going to happen
predict that there will be a difference, but not which direction it will be in
e.g. there will be a significant difference in number of electric shocks given to a stranger after playing an anti-social computer game and after playing a non-aggressive game
null hypotheses
when researcher is confident that the IV will have no effect on the DV
e.g. there will be no difference in number of electric shocks given to a stranger after playing an anti-social computer game and after playing a non-aggressive game
random sampling
every person in target population has equal chance of being selected
obtains a list + computerised random generator used to select required amounts of participants
target population
group of people who share a given set of characteristics about who the researcher wishes to draw a conclusion
obtains just a sample
intend to generalise findings from sample to target population - should be representative of entire population
random sampling strengths
sample likely to be representative
researcher has no control over who is selected - reduces chance of biased sample
improves population validity
random sampling weaknesses
can be difficult and time-consuming
random generator, list of participants required
not time efficient unless small sample
does not guarantee a representative sample
some groups may still be overrepresented or underrepresented
may be less representative than stratified sampling
opportunity sampling
selects anyone readily available and willing to take part
asks people most convenient
opportunity sampling strengths
sample easy to obtain and cost effective
uses most available people around them
sample does not need to be identified prior to research
opportunity sampling weaknesses
sample unlikely to representative
uses most convenient people around them
participants likely to share similar characteristics and backgrounds, reducing population validity
ethical issues
researcher uses first people see and ask them to take part
students may feel pressure to take part of lecturers ask them, creating problems about consent and right to withdraw
volunteer sampling
participants put themselves forward for inclusion - self-select
researcher places advertisement in magazine/newspaper, radio, email, internet, notice board asking for volunteers
place questionnaires and ask people to return answers
volunteer sampling strengths
may be only way to locate particularly niche group of people - volunteer themselves to take part e.g. people with rare medical conditions or people suffering child abuse
can advertise for group otherwise difficult to identify
can save time in gathering sample where niche groups required
volunteer sampling weaknesses
may lack generalisation
likely to be co-operative and motivated (want to spend more time in experiment, rely to give honest, genuine results) and have shared characteristics (psychological studies may involve people interest, know what to look for - demand characteristics)
limits population validity as fails to reflect wide variety of members from target population
may lack generalisation
relies upon people seeing advertisement to put themselves forward - similar characteristics (gym, app, magazine)
limits population validity as reduces size and variability of sample (similar backgrounds, readers of same newspaper)
systematic sampling
every nth member of target population selected
sampling frame produced - list of people in target population organised in some way
sampling system nominated or determined randomly to reduce bias
systematic sampling strengths
avoids researcher bias
once system has been established, researcher has no influence over who is chosen
increases validity and should lead to more representative sample
systematic sampling weaknesses
does not guarantee representative sample
even through randomised, may still be over or underrepresented
less than other methods
time-consuimg
sampling frame and list of target population has to be stablished before selectio
stratified sampling
composition of sample reflects proportions of people in sub-groups / strata within target population
identifies different strata making up population
proportions calculated
participants selected through random sampling
stratified sampling strengths
avoids researcher bias
once subdivided into strata, random sampling method ensures all groups are represented and researcher has no influence over who is chosen
gives accurate reflection of target population leading to higher population validity
stratified sampling weaknesses
time consuming
has to identify strata, proportions, selected randomly
requires knowing all participants and details of sample
not completely representative
identified strata cannot reflect all possible sub-groups - most identified strata likely to be considered but some less noticeable and more personal groups may be ignored
bias
when certain groups may be over or under represented within selected sample
generalisation
extent to which conclusions from particular investigation can be broadly applied to population
made possible if sample is representative
self-report techniques
questionnaires and interviews
gather info from large numbers of people
investigate attitudes or opinions on particular topic
qualitative or quantitative data
questionnaires
written format, less flexibility
no social interaction between researcher and participant
uses standardised procedure
pre-written questions
self-report data (asking people about feelings, attitudes or beliefs)
Likert scales
closed questions
gather quantitative data - easy to analyse
open questions
gather detailed qualitative data
questionnaires strengths
highly replicable
standardised procedure - easily redistribute and check findings for reliability
time and cost efficient
large sample reached quickly and easily - large amount of data gained and analysed + statistical analysis used
investigator effects / researcher bias
researchers not present - cues less likely
questionnaires weaknesses
people may modify answers due to social desirability bias, reducing validity
sample biased towards more literate people - reduces validity and likely to be unrepresentative
researchers not always present, so participants cannot ask for help with unclear questions and may miss sections out, limited amount of info gathered
notes about questionnaires vs interviews
easy to repeat as researcher does no require specific training to distribute - data can be collected from large number of people - high in replicability
respondents may feel more able to reveal personal info (not face to face) - data more likely to be truthful and more valid
closed questions –> quantitative data –> easier to analyse and draw comparisons than open questions –> qualitative data –> difficult to analyse
only certain types of people do questionnaires (depending on where and how distributed), may be sample bias, only people with similar characteristics may do them, decreasing representativeness
interviews
include social interactions
researchers require specific training
asking questions to participant and response recorded or transcribed
gather self-report behaviour
open and closed questions
structured interviews
fixed predetermined questions
large-scale interview based surveys e.g. market research
semi-structured interviews
guidelines for questions to be asked
phrasing and timing left up to interviewer
questions may be open-ended
unstructured interviews
may contain a topic area
no fixed questions
researcher asks questions + further questions depending on answers given
interviewer helps participants and clarifies questions
interviews strengths
more appropriate dealing with complex/sensitive issues - can gauge is participant is distressed or not, can stop research and offer additional support
research is present - interesting issues and misunderstandings can be followed up immediately - richer and more insightful data gathered, increasing validity
lots of rich qualitative data gathered (especially in unstructured interviews) compared to questionnaires as there are fewer constraints in place