week 6 exp design 2 Flashcards
agency
human beings (agents) act upon and shape their environment
interpretation
people perceive, think and make choices to adapt their actions and behaviors
double interpretation
One person interprets how another person interprets, and acts accordingly, which may in turn influence the interpretation and action of the other person.
what did Giddens suggest
Participants interpret the researcher’s behaviour and the setting of the study and adapt their behaviour, which is then interpreted by the researcher.
give 2 agency-based biases in research
- participant effects
- investigator effects
bias
unwanted signal producing spurious results
what are participant effects
cues or triggers of the setting or researcher is interpreted by the ptsp producing response biases
what are investigator effects
behavior of researcher affects ptsp and data producing observer, sampling or selection bias
2 types of investigator effects
primary observer effect - researchers expectations about findings conveyed to ptsp and influence responses eg. self-fulfilling prophecies
secondary observer effects - researchers select and handle data in subjective, biased way
self-fulfilling prophecy
behaving so what you expect will become true
participant reactivity
act of doing exp causes ptsp to alter performance knowing they’re being observers - may happen consciously or unconsciously but produces response bias
response bias
systematic tendencies of ptsp to respond inaccurately producing either a systematic error, or if mixed with investigated effects - a confound
4 types of participant effects
- participant expectancy
- demand characteristics
- social desirability
- stereotype threat
participant-expectancy effects
Participant expects a result and therefore unconsciously affects the outcome or reports the expected result.
give an example of participant-expectancy effect
placebo effect
nocebo effect
negative expectations about treatment causes negative effects eg exaggerated fear of side effects
demand characteristics
Participants form an interpretation of the study’s purpose and subconsciously change their behaviour to fit that interpretation
what is pygmalion effect
Communication between the participant and investigator affect participant responses, e.g., encouraging and discouraging communication
golem effect
low expectations lead to poor performance
2 subtypes of demand characteristics
please you and screw you effects
social desirability
Tendency to answer questions in a manner that is expected to be viewed favourably by others and that produces or maintains a publicly acceptable image.
3 subtypes of social desirability bias
- Bradley effect
- evaluation apprehension
- watching eye effect
what is the bradley effect
When asked in a poll, voters respond they consider voting for a black candidate because they assume that this is socially desirable (politically correct); but in the end, they don’t vote for the black candidate.
what is evaluation apprehension
When being observed, participants feel evaluated and try to convey a positive image.
what is watching eye effect
When being observed, participants try to behave better (or what they assume to be better) than without observation.
stereotype threat
Responses are biased to conform to stereotypes about the participant’s social group.
Can produce response biases in both directions, positive and negative.
give 2 types of positive effects in stereotype threat
stereotype boost and lift
stereotype boost
Perceive yourself better because of positive stereotypes about your own group.
stereotype lift
Perceive yourself better because of negative stereotypes about another group (outgroup).
3 ways to control participant effects
minimise, assess, account for
how to minimize participant effects
- blind procedures -
Information which may influence the participants of the experiment is withheld (masked or blinded) until after the experiment is complete.
- Unobtrusive manipulations and measures: Conceal independent and dependent measures, so they do not provide clues about the research hypothesis.
3.deception - deceive
ethical problems of blind procedures or unobtrusive methods
impossible to gain consent eg when recording
danger eg observing bullying
how to asses participant effects
post-experiment questions eg “did you know what was expected?”
how to account for participant effects
control conditions - have baseline for reference
randomized control tries
placebo control trials
what does bias due to secondary observer effects during data sampling produce
sampling bias
what does bias due to secondary observer effects during data recording and interpretation produce
observer bias
what does bias due to secondary observer effects during data analyses produce
selection bias
2 types of observer bias
- cognitive bias
eg confirmation bias - A tendency to search for, interpret, favour, and recall information in a way that confirms or supports one’s prior beliefs, values, or hypotheses.
eg halo effect - endency for the positive impressions and beliefs in one area to influence a researcher’s data recording or interpretation in other unrelated areas. - detection bias
focusing on some cases to the detriment of others, e.g., checking diabetes in obese but not other patients, hence skewing the prevalence of diabetes in obese people.
how to minimize investigator effects
double - blind procedures = participant and researcher are unaware of the allocation to experimental conditions and cannot anticipate any result.
how to asses investigator effects
observer reliability - indicates how consistent the results are
2 ways of assessing reliability during investigator effects
inter-observer relaibility = across different observers
intra-observer reliability aka test retest = within observer
how to account for investigator effects
averaging across several researchers compensates for individual biases eg jury ratings
if the bias DOESNT confound with effects you want to measure it is a…
systematic error
if the bias does confound with the effects you want to measure it is a…
confounding variable
participant and investigator effects decrease…
internal and external validity
statistical sample
the entire pool (or set) of people, items, or events, about which a researcher wants to gain insight and draw conclusions in a study.
statistical sample
a set of individuals or objects collected or selected from a statistical population by a defined procedure (i.e., sampling). = a subset of the population.
sampling
the selection of a subset (i.e., sample) of individuals from within a statistical population to estimate characteristics of the whole population.
what does systematic error in sampling cause
some members of the intended population to be less likely to be included in the sample (higher sampling probability) than others - low external validity
non-probability sampling
non-random selecting producing bias eg volunteering, opportunity or snowball sampling
what types of sampling bias is produced from non-probability sampling
exclusion bias - missing particular groups of sample
self-selection bias - eg people with specific characteristics more likely to agree to study than others
probability sampling
random selection produces representative sample
3 methods to probability sampling
- simple random sampling
- systematic sampling
- stratified sampling
systematic sampling
Starting from a random number, every nth person from a list is selected
stratified sampling
STRATUM = sub-population.
* STRATIFICATION = dividing members of the population
into homogeneous subgroups before sampling.
* If you know beforehand that there are different subgroups in the population.
* Each stratum is sampled randomly as an independent sub-population
* The number of individuals per stratum is proportional to the size of strata in the population.
population validity
is participant sample representative
ecological validity
is stimulus sample representative
stages of research projects
- funding
- ethical approval
- empirical study - prepare and collect data
- dissemination - submit manuscript for publication, review eg peer review
