Scientific Processes Flashcards
define opportunity sampling and evaluate
particiapnts happen to be avaliable at the time the study is being done - recruited conveninetly
* time saving and less costly
* not representative of whole poopulation= lacks generalisability
* researcher bias - they control who they want to select
define random sampling and evaluate
all members of a population have the same equal chances of being the one that is selected
- each meber of the population is assigned a number then random number generator is used to randomly pick
* no researcher bias - no influecne over who is picked
* time consuming - neeed to have a list of members of population (sampling frame ) and contracting them
* volunteer bias - particiapnts can refuse to take part so sample can be unrepresentative
define systematic sampling and evaluate
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a predetermined system is used where everu nth member is selected from sampling frame. selection is applied consistently
* avoids researcher bias and usally fairly representative of popualtion
* not truly unbiased unless use a random number generator
define stratified sampling and evaluate
compostion of sample reflects the varying proportions of people in subgroups within wider population
- identify strat
- calcuate the required proprtion needed for each stratum based on target population
- selct sample at random from each stratum using random selection method
- no researcher bias- stratum selction is random
- produces representative data due to proportional strata
- time consiming to identfy strata and contact people from each
- complete representation of target population is not possible as the indeified strata cannot reflect all the differences between the people of the wider popualtion
define volunteer sampling and evaluate
self selection- participant offers to take part in study
* quick access to willing partipant = not time consuming
* particiaptns are more likely to cooperate in the study
* volunteer bias - study may attract a particular profile of a person = affects generalisability
* motivations like money could be driving participant= may not tkae study seriously
what is the differnce between popualtion and sample
population is a gorup of people from who the sample is drawn
hypothesis
statment that states the relationship between the variables being investigated
- directional/ one tailed
- non directional/ two tailed
- null hypothesis
- alternative
- iv operationalised
- dv operationalised
- direction
- both conditions
EG: particpatns who attend a revison session will have higher test scores than those who dont attend a session
hypothesis should be non directional:
* no previous research
* inconsistent findings
define an aim
statment made by researcher tell us what they plan on investigating and the purpose fo the study
define extraneous variables
any other variable taht is not the IV that affefcts the DV and does not vary systematically with teh IV
* lighitng in lab
* age of participants
define cofounding variables
variable other than IV that effects DV. they do not change systematically with the IV = difficult for researcher to be sure of origin and impact on DV
eg: sleep
define demand characteristics
any cue the researcher or situation may give which makes the participant guess the aim of the investigation
cause participant to act differently
participant reactivity- from start try and guess aim
- “please U effect”- act in a way they think researcher wants them to
- “screw U effect”- unintentionally underperform to sabotage the results
= effects valdity
define investigator effects
caused by participant reactivity
unwatned infleuce from the researcher behaviour - conscious or unconscious- on the DV
* design of the study
* selection of participants
* interaction with each particpant
how to prevent demand characteristics
- single blind studies
- matched pairs
- double blind
how to prevent investigator effects
- double blind
- randomisation sample
- counterbalancing (controlling order effects in repeated measures design)
- standardisation - participant told to do excat same thing
define randomisation
*to minimise effects of extraneous or cofounding variables
*use of chance to reduce effects of investigator effects:
* done for the design of materials
* order of conditions
* selection of participants
define standardisation
*to minimise effects of extraneous or cofounding variables
*using exact same formalised procesdures and instructions for every single participants
= eliminates non standardised instructions as a extraneous variable *
define and evaluate indepdendent groups
particiapnts only perfome in one codition of IV
* no order effects
* participatns are less likely to guess aim = demand characteristics are eliminated
- need more particiapnts
- no contorl over participant variables = can cause chnages to DV
= random allocation- ensures that each particiapant has the same chance of being in one condtion of IV as another
define repeated measures design and evaluate
same particiapnt takes part in all condtions of IV
* eliminates particiapnt variables
* fewer particiapnts needed = not as time consuming
- order effects presented EG boredom
= counterbalancing - particiapnts do conditions in one order and other hald do it in an opposite order
define and evlauate matched pairs
pairs of participants are matched on some variable that has been found to affect DV
* no order effects
* reduced demand characteristics
- time consimung and expensive to match
- large pool of particiapnts is needed which is hard to get
- difficult to know what variables are appropriate for participants to be matched on
define pilot study
small scale version of an investigation done before real invesitgation
* allow potential problems to be indeifiied
* procedure can be modified
* money and time saved
define single blind procedure
researchers do not tell participants if they are being given a test treatment or a control treatment
* to avoid demand characteristics
define double blind procedure
neither participants or experimenter knows who is receving a particular treatment
* prevent bias of demand characteristics
* prevent placebo effect
* reduce investigator effects
define behavioural categories
target behaviour which is being observed is broken up into mor precise components which are observable and measurable
eg: aggressive behaviour- punching shouting swearing
important to make sure behaviours do not overlap with other behaviours + should be operationalised
define and evaluate time sampling
recording of behaviour within a time frame that is pre established
* reduced number of observations= less time consuming
* small amount of data collected within time frame ends up being unrepresentative of the observation as a whole
define and evaluate event sampling
counting the number of times a particular behaviour is carried out
* good for infrequent behaviour that would of been missed in time sampling
* if complex behvaiours are observed- important details of behaviour may be overlooked
* counting errors
* difficult to judge beginning and ending of behaviour
define and evaluate peer review
to knwo which research is worthwile = funding
validate the relevance and quality of research
suggest improvements or amendments
- anoymity is a problem: can affect objectivity eg bury rivals
- publication bias- file drawer problem - negative results are intentionally not bias = misconception of psychology
- rate of change in scientfic fields is slowed down- research to oppose main stream theories tend to be suppressed
implications of psychological research for the ecnomy
what we learn from research influences economy
psychopathology: treatments= workers able to return to work
attachment: role of father = mpthers returnt to work + flexible working arrangments
social influence: minority influence= health and environemtal campaigns eg use of non renewable energy
memory: eyewitness testimony - cognitive interview= reduced wat of money and space in jail (prevents wrong convictions)
define and evaluate case studies
detailed study into the life of a person = qaulitative data
eg : HM memory - different types of long term memory
- depth insight
- forms basis for future research
- can understand unusal behaviour that otherwise would be unethical or impractical
- not generalisable to wider population
- varaious interviewer biases - social desirability bias and interpretative biasis
- time consuming and difficult to replicate
define scientific report
abstract: summary of key details of research report - if research study is worth examining
introduction: info of past research - theories and concepts
method: description of what researcher excatly did - detail to replicate
results: all findings
discussion: considers what findings mean for psychological theories
refernces: list of all sources
define reliability
measure of how consistent the finings from an investigation are
* ensure DV is being measured accurately
* ensure that outcome is the same over a period of time
* ensure conclusions made are accurate and not have implications for theory development
define internal reliabilty and way of assesing
how consistent something is within itsefl
split half method randomly select half of the questions and put them in one form then do the same for others. two forms of the same test are done seperattely and shoukd yield the same score and have a correlation coefficent of >_ 0.8
define external reliability and ways of assessing
consistent results are produced regardless of when the investigation is sued or who administers it
test retest method: researcher administers the same test on the same person on different occasions. should yield a correlation coefficient of >_0.8
enough time so cannot recall answers but not too long to change a perosns attitude
inter observer reliability: refers to the extent to which there is agreement between or two or more observers for behaviour. this eliminates subjectivity bias >_ 0.8 is high
ways of improving reliability
questionaires - replace open questions where there may be misinterpretations with fixed questions which may be less ambiguous
interviews- not ask leading or ambiguous questions
experiments- researcher can exert strict control over many aspects of the procedure such as intructions that participants recieve and the conditions within which they are testes = replicable
observations- behavioural catergories have been operationalsied = measurable. should not overkap
define validity
extent to which results of a researcher study are legitimate
define internal validity and ways of assessing
whether the outcomes observed in an experiment are due to the manipulation of the iV and not any other factor
influenced by:
* cofouding and extraneous variables
* participant variables adn demand characteristics
* investigator bias
define external validity
factors outside the investigation - generalisable to other se
