research methods Flashcards
what is an aim?
a general statement of what the researcher intends to investigate - purpose of the study
what is a hypothesis? what is a directional and non-directional hypothesis?
- statement made at start of a study and clearly describes relationship between variables as stated by a theory
- needs to make it easy to tell what IV and DV are
- directional - researcher makes clear sort of difference anticipated between 2 conditions or two groups of people - include words like more/less, higher/lower, faster/slower
- non-directional - simply states difference between conditions/groups
what are independent and dependent variables? how should other variables potentially affecting the DV be treated? why?
- in experiment - researcher manipulates independent variable + records/measures effect of change on dependent variable
- all other variables that might potentially affect DV should remain constant in a properly run experiment
- so researcher can be confident any change in DV due to IV alone
why should we check levels of IV? how would we?
- in terms of energy drink. if simply gave ptps speedup, how would we know how talkative they were?
- in order to test need different experimental conditions - need a comparison
- could either: compare ptps talkativeness before + after drinking
- compare two groups: those who drink energy drink + those who drink water
- the two levels of IV - control condition (no energy drink/drink of water) and experimental condition (energy drink)
how do you operationalise variables in a hypothesis?
- make the variables measurables
- ex. after drinking 300ml of energy drink, ptps say more words in next 5 mins than ptps who drink 300ml water
what are extraneous variables? what are examples? what are their effects?
- independent variable is manipulated to see how it affects the DV
- only thing that should affect DV is IV
- any other variables that might potentially interfere with IV should be controlled/removed
- additional unwanted variables called EV
- age of ptps
- lighting in lab
- ‘nuisance variables’ do not confound findings - may just make it harder to detect result
what are confounding variables?
- do change systematically with IV
- can’t tell if any change in DV due to IV or confounding variable (almost like a second unintended IV)
what are demand characteristics?
- any cue from researcher/from research situation - may be interpreted by ptps as revealing purpose of investigation
- may lead ptp changing behaviour within research situation
- may act in a way they think is expected + overperform (please-U effect) or opposite to sabotage results (screw-U effect)
- unnatural ptp behaviour - extraneous variable may affect DV
what are investigator effects?
- any effect of investigator’s behaviour (conscious/unconscious) on research outcome (DV)
- can include everything from design of study to selection of + interaction with ptps during research process
what is randomisation?
- minimise effect of extraneous/conf variables on outcome
- use of chance methods to reduce researcher’s unconcscious bias when designing investigation
- controls investigator effects
- in exp where ptps involved in number of conds - order of conds should be randomly determined
- if all ptps were to take part in all conds - order of completion would need to be randomised for each ptp
what is standardisation?
- all ptps should be subject to same environment, info + experience
- to ensure all procedures standardised - list of exactly what will be done in the study
- standardised instructuctions that are read to each ptp
- such standardisation means non-standardised changes in procedure do not act as extraneous variables
what is an experimental design?
different ways in which ptp’s can be organised in relation to the experimental conditions
what are the different experimental designs?
- independent groups design
- repeated measures
- matched pairs
what is an independent groups design?
- when two seperate groups of ptp’s experience two different conditions of the experiment
- if there are two levels of the IV - means all ptps experience one level of IV only
- performance of two groups then compared
what is an example of an independent group?
- one group of ptp drinking energy drink (condition A - experimental condition)
- a different group (group2) drinking water (condition B - control condition)
- performance compared : mean number of words spoken in the 5 min period after drinking for each group/condition
what is a repeated measures design? use the energy drink example
- all ptp’s experience both conditions of experiment
- ex. each ptp would first experience condition A (energy drink condition)
- ptp would then later be tested again in condition B (glass of water condition, control condition)
- following this, the two mean scores from both conditions would be compared to see if there was a difference
what is a matched pairs design?
- ptp’s paired together on a variable/variables relevant to experiment
- ex. memory study - might be matched on IQ - good indicator on ability to recall
- two ptps with first + second highest IQ paired together + the one with 3rd and 4th highest and so on
- then one ptp from each pair allocated to a different condition of the experiment
- attempt to control for the confounding variable + ptp variables
how would matched pairs be used in the energy drink example?
- observe ptp’s interacting in a room before ex begins + select 2 which most chattiest - one pair placed in condition A + other condition B and so on
- then ex will run in same way as indep group design
what is an issue with independent groups when it comes to ptp variables? how can it be dealt with. what is an issue of it compared to RMD?
- ptp’s who occupy the different groups not the same in terms of ptp variables
- if researcher finds a mean difference between groups on dependent variable - may be more to do with ptp variables than effects of IV
- may act as confounding variable - reducing validity
- to deal with it they use random allocation
- less economical than repeated measures - each ptp contributes a single result only - twice as many ptp needed to produce equivalent data to that collected in a repeated measures design - increases time + money spent on recruiting ptp
what are strengths of independent groups? compared to RMD?
- order effects not a problem - whereas problem for repeated measures design
- ptp’s less likely to guess aims
what are the issues of the RMD? explain effects of order using energy drink example. how else can order effects happen? how can an order effect be a confounding variable?
- each ptp has to do at least two tasks + order of these tasks may be significant (order effects)
- energy drink: having energy drink first may have a continuing effect when ptp drinks water afterwards
- could arise because repeating two tasks could create boredom/fatigue - might cause deterioration in performance on second task - order matters
- alternatively - ptps performance may improve through effects of practice - esp on a skill-based task - in this case ptps will perform better on second task - order effect confounding variable
how is demand characteristics a problem for RMD?
- more likely ptp will work out aim of the study when experience all conditions of experiment
- hence why DC tend to be more of a feature of RMD than indep groups
what is a strength of RMD?
- ptp variables controlled - therefore higher validity
- fewer ptp needed (less time recruiting)
what are strengths of matched pairs?
ptp only take part in single condition - order effects less of a problem
what are disadvantages of matched pairs?
- although some attempts to reduce ptp variables - ptp can never be matched exactly - even when identical twins used - will be important differences between them may affect DV
- matching may be time-consuming + expensive - particularly if pre-test required - less economical than other designs
what are the different types of experiments?
- laboratory experiments
- field experiments
- natural experiments
- quasi-experiments
what is a laboratory experiment?
- conducted in highly controlled environments
- not always a lab
what are the strengths of a lab experiment?
- high control over confoundings + extraneous variables
- ensure effects on DV result of manipulation of IV - more certain about demonstrating cause + effect (high internal validity)
- replication more possible than in other types of ex because of high level of control - ensures new extraneous variables not introduced when repeating an experiment
- replication vital to check results of study - whether findings valid + not just one-off
what are the limitations of a lab study?
- may lack generlisability - lab environment may be rather artificial + not like everyday life
- ptp’s behaviour may be different + cannot be generalised beyond research setting (low external validity)
- ptps usually aware being tested in lab ex (DC)
- tasks may not represent every day experience (low mundane realism)
what is a field experiment?
- IV manipulated in a natural - more everyday setting
- researcher goes to ptp’s usual environment rather than going to a researcher’s lab
- researcher manipulates the IV + records the effect on the DV
what are the strengths of a filed experiment?
- higher mundane realism than lab experiments - environment more natural - may produce behaviour which is more valid + authentic
- especially case as ptps may be unaware they are being studies (high external validity)
what are the limitations of a field experiment?
- loss of control over CVs and EVs - means cause + effect between IV and DV in field studies may be much more difficult to establish + precise replication often not possible
- ethical issues - ptp unaware they are being studied - cannot give consent to being in studies + such research constitute to invasion of privacy
what are natural experiments?
- takes advantage of pre-existing IV in environment
- lab/field experiment insofar as the researcher measures effect of IV/DV - researcher no control over IV + cannot change - someone/something else causes IV to vary
(ex before/after natural disaster) - iv that is natural not necessarily setting - may even be tested in lab
- DV may also be naturally occurring/ devised by experimenter + then measures in field/lab
what are the strengths of a natural experiment?
- provide opportunity for research may not otherwise be undertaken for practical/ethical reasons
- high external validity - involve study of realworld problems as they happen . ex effects of natural disaster on stress levels
what are the limitations of a natural experiement?
- naturally occurring event may only happen very rarely - reducing opportunities for research
- ptps maynot be randomly allocated to experimental conditions (when there is an IGD) - may mean less sure whether IV affected DV
- such research may be conducted in a lab - lack realism + DC
what is a quasi-experiment/
- researcher takes advantage of a pre-existing IV within a person
- does not manipulate IV
- DV may be naturally occurring/ devised by experimenter + measured in field/lab
what are the strengths of a quasi-experiment?
- often carried out under controlled conditions - share from strengths of a lab ex (replication)
what are limitations of a quasi-experiment?
- like natural experiments - cannot randomly allocate ptp to conditions - therefore may be CVs
- both quasi + natural - IV not deliberately changed by researcher - cannot claim IV caused any observed change
what is a population?
- large group of individuals that particular researcher interested in studying
- often called target population - subset of general pop
what is a sample?
- practical + economic reasons - usually not possible to include all members of target pop - so researcher selects smaller group - sample
- ideally representative - so generalisation of findings become possible
- however difficult to represent pop due to diversity - so majority - some degree of bias
what are the sampling techniques which aim to produce a representative sample?
- random sample
- systematic sample
- stratified sample
- opportunity sample
- volunteer sample
what is a random sample?
- sophisticated form of sampling - all members of target pop - equal chance of being selected
- first step is to obtain complete list of all members of target pop - second all names on list assigned number
- finally - actual sample selected through use of some lottery method
what is a systematic sample?
- when ever nth member of the target pop is selected - ex every 3rd house on a street
- sampling frame produced - list of people in target pop organised into, for instance, alphabetical order
- sampling system nominated (every 3rf, 6th etc person)
- may begin from a randomly determined start to reduce bias
- researcher then works through sampling frame until sample complete
what is a stratified example?
- sophisticated form of sampling in which composition of sample reflects proportions of people in certain subgroups (strata) within target pop/wider pop
- researcher first identifies different strata that make up the pop
- proportions needed for sample to be representative worked out
- finally ptps that make up each stratum selected using random sampling
what is an opportunity sample?
- given that representative samples of target pops difficult to obtain
- many researchers simply select anyone who happens to be willing + available
- ask whoever is around at the time of their study
- ex. in street
what is a volunteer sample?
- involves ptp selecting themselves to be part of sample (also referred to as self-reflection)
- researcher may place advert in newspaper
what are advantages of a random sample?
- potentially unbiased - confounding/extraneous variables should be equally divided between different groups - enhancing internal validity
what are the disadvantages of a random sample?
- difficult + time-consuming to conduct - complete list of target pop may be difficult to obtain
- may end up with a sample that is still unrepresentative
- selected ptps may refuse to take part (end up with something more like a volunteer sample
what are the disadvantages of a systematic sample?
- objective
- once system for selection established - researcher no influence over who is chosen
- method time-consuming - and in the end ptp may refuse to take part resulting in a volunteer sample
what are the advantages of a stratified sample?
- produces a representative sample - designed to accurately reflect composition of population - generalisation of findings possible
what are the disadvantages of a stratified sample?
- not perfect
- identified strata cannot reflect all the ways people are different - complete representation of target pop not possible
what are the advantages of an opportunity sample?
- convenient - much less costly in terms of time + money compared to ex. random
- as list of target pop not required + no need to divide pop into different strata as there is in stratified sampling
what are the disadvantages of an opportunity sample?
- suffers from two forms of bias
- sample unrepresentative of target pop - drawn from a very specific area - findings cant be generalised to the target population
- researcher has complete control over selection of ptps - researcher bias may be possible
what are the advantages of a volunteer example?
- collecting volunteer sample easy
- minimal input from researcher - less time-consuming than other forms of sampling
- ends up with ptps who are more engaged than someone stopped on the street
what are the disadvantages of a volunteer sample?
- volunteer bias
- asking volunteers may attract a certain ‘profile’ of person - curios + more likely to try to please researcher (might affect how far findings can be generalised)
what are ethical problems that face ptps and and researchers face?
- informed consent
- deception
- protection from harm
- privacy + confidentiality
what is informed consent?
- prospective ptps in studies should know what they are getting into
- informed consent making ptps aware of aims of research, procedures + their rights (including right to withdraw) + what data will be used for
- ptps then make informed judgement whether or not to take part without being coerced/feeling obliged
- but asking for informed consent may make study meaningless - ptps behaviour not ‘natural’ - know aims of study
what is deception?
- deliberately miselading + withholding info from ptp
- ptp’s who have not received adequate info when agreed to take part - cannot be said to give informed consent
- occasions when can be justified - if dont cause distress
what is protection from harm?
- must be protected from physical + psychological harm
- same mental state they joined the study with
- important feature of this is ptp being reminded of the fact they have right to withdraw from investigation at any point
what is privacy and confidentiality?
- right to control info about themselves
- confidentiality - refers to our right - to have any personal data protected
- right to privacy extends to the area where the study took place - institutions/geographical locations not named
what is the bps code of conduct?
- ethical guidelines - have professional duty to observe these guidelines when conducting research - may lose their job
- guidelines implemented by ethics committee in research institutions who often use a cost-benefit approach to determine whether particular research proposals are ethically acceptable
how do researchers deal with informed consent?
- ptp should be issued with a consent letter or form detailing all relevant info that might affect their decision to participate
- assuming ptp agees - this is then signed
- for investigations involving under 16 - parental consent
how should researchers deal with deception + protection from harm?
- at end ptp should be given full debrief - made aware of true aims of investigation + any details not supplied during study
- also told what data will be used for + must be given the right to withdraw during study + right to withhold data
- must be reassured their behaviour was typical during investigation - if ever subject to anything researcher should provide any counselling
how should researchers deal with confidentiality?
a - if personal details held - must be protected
- more usual to maintain anonymity - usually refer to ptp as initials/numbers
- standard practice - during briefing+debriefing - ptp reminded data will be protected throughout process + told data will not be shared to other researchers
what are the different types of consent?
- presumptive - rather ptp themselves - given by a similar group of people
- prior general consent - ptp gives permission to take part in a number of different studies - including one that will inlove deception - consenting to be deceive
- retrospective consent - ptp asked for their consent after taking part - may have been deceived/ not been aware of participation