research methods - cog Flashcards
cognitive approach
how information is processed in the brain
what is an experiment?
a scientific procedure undertaken to test a hypothesis in order to demonstrate casual relationships
hypothesis
statement of what a theory predicts
laboratory experiment
occurs in a controlled artificial environment
field experiment
occurs in a natural environment
lab experiment - strengths
very scientific - hypotheses tested in a fully controlled environment
standardised procedure usually used - easy to repeat
participants are normally aware they are taking part - can give informed consent
lab experiment - weaknesses
time consuming to design and conduct
difficult to recruit participants
expensive
participants likely to guess the aim of the study and therefore behave differently
field experiment - strengths
shows natural behaviour but is also controlled
field experiment - weaknesses
doesn’t have full control over variables - cannot be replicated easily
operationalisation
making the variable clear and precise
experimental group
the group where the variable is manipulated to see if there is an effect
control group
the group where nothing is manipulated so it acts as a baseline for comparison
random allocation
randomly allocating participants to independent variable conditions means that all participants have an equal chance of taking part in each conditon
directional hypothesis
states the direction in which the results are expected to go
non-directional
doesn’t make any claim to which way the results may go
null hypothesis
a statement of no difference
independent measures
different participants are used in each condition of the independent variable
independent measures - strengths
avoids order effects
makes guessing the aim unlikely
independent measures -weaknesses
participant variables
- individual differences
- solution : randomisation
requires a large amount of participants
chances of obtaining the true aims of the experiment are lower
repeated measures
each condition of the experiment includes the same group of participants
repeated measures - strengths
suits research when only a small amount of participants are available
controls participant variables
repeated measures - weaknesses
order effects
- practice effect
- fatigue effect
- solution: counterbalancing
participants may guess aims
matched pairs
participants are matched in terms of key variables and then one member of each pair in placed into the experimental group and into the control group
matched pairs - strengths
avoids order effects
controls participant variables
matched pairs - weaknesses
experimenter effects - the experimenter has had to choose who to match
time consuming
costly
doesn’t control all participant variables
counterbalancing
the participant sample is divided in half, with one completing the two conditions in one order and the other half completing the conditions in the reverse order