research methods Flashcards
experiments
- studying people with fixed conditions (variables)
- finding if changing one variable causes a change in another
- testing a hypothesis
EX: drug effective in treating people with depression
correlational studies
- collecting lots of data on people
- looking for patterns (correlations)
EX: income level impacting likelihood of getting a divorce
case studies
- in depth investigation (case)
- normally on a person who is unique in some way
- finds information on human nature or rare diseases
EX: someone with a really good memory to find out more on how our memories work
independent variable
- what the psychologist is exploring to see if it is the cause of behaviour
- manipulated
- usually different groups for reliability and each group will get different “levels” of IV
dependent variable
- outcome that is measured
- if the hypothesis is correct then when the independent variable is changed this will cause a change of the dependent
extraneous variables
- other variables that may impact the results
- should be controlled to make sure it really is the independent variable impacting the dependent variable
- if these aren’t controlled correlation ≠ causation as it could just be the independent variable
laboratory experiments
pros
- easy to control extraneous variables
- easy to replicate and confirm
cons
- participant bias meaning they won’t act how they normally will because they know they are being observed
- want to look good
field experiment
pros
- because it is in a natural setting, more likely to reflect how participants behave in everyday life
- high ecological validity
cons
- very hard to control all extraneous variables as the environment is constantly changing
- music might start playing, sun sets, new people arriving and leaving
natural experiment
pros
- independent variable changes naturally so psychologists can study things that would be unethical (disease) or impossible to create (volcano)
- reflect how people behave in everyday life
cons
- usually only one time events which are unable to be replicated
issues with experimental research - participant variability
participant variability
- participants in seperate groups being different which will impact the results
- only trying to find the independent variable
- groups need to be as similar as possible
- to solve this randomly assign participants to groups and have a large even range of types of participants
- each group will roughly have the same characteristics with no major differences
issues with experimental research - demand characteristics
demand characteristics
- participants trying to guess the purpose of the experiment from subtle cues
- thinking they know the purpose will cause them to behave unnaturally either aligning with what they think the purpose is or doing the opposite
- to solve this researchers should keep the hypothesis secret or even mislead participants (ethical issues)
issues with experimental research - researcher bias
researcher bias
- subconsciously or consciously designing the experiment to fit the results they want to see
- drop hints to participant to encourage certain behaviour
- ignoring results that don’t support their theory
- to solve this researchers could implement a double blind which is where neither the participant or the psychologist knows which is placebo or the real thing
- used mostly in medicine
sample
- selecting a small group within a population to represent the whole
- need to make sure your sample is representative of the target population
- representative = generalizable
convenience sample / opportunity sample
- asking whoever is there if they want to participate
pros
- quickest and easiest way to obtain participants
cons
- sample may not be representative since it is only people in that location at that time
- can really only be done in studies that take a few minutes
self-selected sample / volunteer sample
recruiting people who volunteer to participate in a study usually in exchange for payment
pros
- easy way to obtain participants
- as they volunteered they are more likely to cooperate and be motivated
- no ethical issues as it is free will
cons
- people who choose to volunteer may be different to those that don’t
- may not be representative of target population
- fearing being judged or reported to the police possibly
snowball sampling
participants are asked to refer other people they know like family or friends who would also be willing to participate
pros
- easy way to obtain participants especially with populations that are hard to contact
- ie drug dealers, but once the trust of one has been gained other members of the target population will feel safe to participate
cons
- all come from the same social circle which may not be representative of the target population
- ie all from the same drug ring, won’t hold the same views as others from different sections
- not much anonymity as names of people participating know each other
random sampling
everyone in the population has an equal chance of being sampled, often used for samples before an election.
pros
- very representative sample so information can be generalized
cons
- expensive and time consuming
- no guarantee that the random people will agree to participate
- can cause response bias, different views of people who choose to participate vs those who don’t
positive correlation
- one variable (x) is associated with an increase in the second variable (y)
EX: highly educated people earning more money
negative correlation
- one variable (x) is associated with an decrease in the second variable (y)
EX: physical activity and blood pressure
the less you exercise the higher your blood pressure will be
no correlation
- one variable (x )has no impact on the second variable (y)
EX: height and intelligence
