types of experiments Flashcards
experiments
All experiments involve a change in the IV and the effect on the DV is recorded/measured.
lab experiment
high controlled environments.
stengths of lab ex
high control over confounding variables and extraneous variables, internal val.
replication more possible bc high level of control, no extraneous variables not introduced when repeating.
valid not one- off.
limitations of lab ex
lack generalisability, artificial settin doesnt reflect life, ppts behave unusually in unfamiliar contexts, low external validity
aware tested in lab, demand charateristics.
tasks may be artificial, low mundane realism
field experiment
IV manipulated in natural setting.
strength of field ex
higher mundane realism, environment natural, valid results, high ex validity.
limitation of field ex
loss of control over CV and EV, cause and effect between IV and DV more difficult to establish, precise replication not possible
ethical issues, unaware so cant consent to being studied, invasion of privacy.
natural experiment
Researcher measures effect of IV on DV but has no control over IV and cannot change it. setting may not be natural, DV may be naturally occurring.
strength natural ex
provide opportunitiesfor research that may not otherwise be taken for practical/ethical reasons.
eg romanian orphan studies
high external validity.
limitations of natural ex
naturally occuring events happen rarely, reducing opportunities, limit scope for generalising findings to similar sitches
ppts not randomly allocated to experimental conditions, less sure if IV affected DV.
quasi- experiment
have an IV based on existing difference between people (age or gender), not manipulated, simply exists.
dv naturally occuring,
strength quasi experiment
controlled conditions, replication high.
negative quasi ex
cant randomly allocate ppts, confounding variables.
IV not deliberatley changed by researcher, cannot claim Iv caused observed change.