Research Methods Flashcards
(253 cards)
cause and effect
psychologists use the experimental method to identify the “effect” one variable has on another variable, in other words does one variable ‘‘cause’’ the other variable to change
being able to conduct research that establishes cause and effect is a key feature of scientific research
In a true experiment, there must be …
a control condition and an experimental condition and participants must be randomly assigned to these conditions
this is so that the researcher can make fair comparisons between the two groups
IV DV controlled
a researcher manipulates the independent variable in order to test its effect on the dependent variable
everything else is kept the same (controlled) between the two conditions
if there is a significant difference in the results of the two groups …
we can conclude that the independent variable caused the change in the dependent variable (cause and effect)
IV
independent variables
a variable that is manipulated by the researcher - or changes naturally
DV
dependent variable
the variable that is measured by the researcher. any effect on the DV should be caused by changes in the IV
in order to test the effect of the IV …
we need different experimental conditions
control condition
provides a baseline measure of behaviour without experimental treatment
experimental condition
the one in which there has been researcher manipulation. this is the condition in which the researcher is particularly keen to see if a difference in behaviour has occurred
operationalism
clearly defining variables so they can be measured
aim
general statement of what the researcher intends to investigate, essentially the purpose of the study
hypothesis
a testable statement predicting the outcome of the study which is made at the start of the study
what are the two different experimental hypothesis
directional (one tailed)
non-directional (two tailed)
directional hypothesis
makes it clear what sort of difference or relationship is between the 2 conditions mainly using words like ‘less’ ‘lower’ ‘more’ ‘higher’
what are the two different kinds of hypothesis and explain them
null hypothesis - this predicts that there will be no difference or relationship
alternate/experimental hypotheses - these predict a difference or relationship and can be directional or non-directional
non-directional hypothesis
used when there has been no previous research to suggest what direction the research will go in or the previous findings have been contradictory
‘will be a difference’ or ‘there will be a relationship’ between the 2 conditions but the there is no direction of the outcome
types of experiments
laboratory experiments
quasi experiments
field experiments
natural experiments
lab experiments
conducted in highly controlled environments
researcher manipulates the IV and records the effects of the DV
participants in a lab experiment can be randomly allocated to conditions
a lab experiment is therefore considered a ‘true’ experiment
strengths of lab experiments
high control over extraneous variables meaning cause and effect can be established
replication is possible due to the high level of control. This also means results can be checked for reliability
limitations of lab experiments
participants are often aware of being tested - possible demand characteristics
artificial environment means it may lack generalisability
investigator effect may occur (unless it is a double blind experiment - this is when both the participants and the researcher conducting the experiment does not know the aims of the investigation)
field experiments
researcher still manipulates the IV and records the effects on the DV but the experiment is conducted in a real life setting
strengths of field experiment
high ecological validity due to being conducted in a real-life setting
behaviour is likely to be more valid & authentic (less demand characteristics)
limitations of field experiments
there is less control over extraneous variables (these will be different depending on the experiment)
it is difficult to replicate them completely because they tend to be less controlled
possible ethical issues if participants are unaware they’re being studied
standardisation
this is using exactly the same procedure for all participants, such as the same environment, instructions and experience