Experimental Method Flashcards
What do psychologists do
They come up with a theory and prediction then experiment it and create an observation
what is a hypothesis?
Directional hypothesis?
Non directional hypothesis?
null hypothesis? +
hypothesis = A precise testable statement about the assumed relationship between variables (predictions)
Directional hypothesis = (Already has some evidence) A change in the direction and the change is stated e.g. Girls will get better grades than boys
non-directional hypothesis = ( No evidence ) where it predicts the change but not the direction e.g. there will be a difference in gcse result’s between boys and girls
null hypothesis = states no significant difference exists e.g. There will be
no relationship between boys and girls gcse results
what is the independent/ dependant variable and operationalisation
independent = thing you change
dependent = Thing you measure
operationalisation = clearly defining the variables in terms of how they can be measured
Are these examples directional or non-directional?
“lack of sleep affects reaction time “
“ girls talk more than boys “
“the faster you drive the more likely you are to crash”
“ the quality of service in a restaurant affects its popularity”
non-directional
directional
directional
non-directional
what are extraneous variables
any variable other than the iv that affects the dv if not controlled.
what are extraneous variables divided into and there definitions
demand characteristics = any clue from the researcher that the participants may interpret to reveal the purpose of the investigation (participants may change there behaviour )
investigator effects= Any effect of the researchers behaviour on the out come of the research e.g. bias
participant variables = individual difference’s such as IQ, sleep, gender, age
situational variables = environmental differences such as noise, lighting , instructions, how close the screen is
how can psychologists control extraneous variables in an experiment?
standardisation = using the exact same instructions for all participants ( high control )
randomisation = use of chance to control the effects of bias when designing materials and order of conditions.
what is the study of control vs realism
and mundane realism
if the set up of a study is too artificial then the participant’s will not act as they would normally. Mundane realism refers to how an experiment mirrors in the real world meaning if something is lacking mundane it means its not like real life so cant be used.
Write a hypothesis
participants were told they would be placed in a booth and would have to read out an article to an audience but they cannot see them but only hear them and cannot interact with them
condition A - 10 participants were told they have an audiance of 5 listeners
condition B - the other 10 were told they had a audience of 100
each participant completed the study individually. The psychologist recorded the presentations and counted the number of verbal errors made by each participant
” There will be a difference in the number of verbal errors made by people reading to 5 people compared to people reading to 100 people”
what is the repeated measure design
There is only one group of participants. This group takes part in both conditions ( experiences both levels of the iv )
What are the positives and limitations of the repeated measures design
positives = participant variables are eliminated
limitations = may be more confident the 2nd time around
may have situational factors as an issue
may get bored
( ORDER EFFECTS e.g. practise, fatigue )
what is experimental design
How participants are allocated to the different conditions in an experiment
How to deal with the limitations in the repeated measures design
Half of the participants do A first then B. Then the other half do B then A
( counterbalancing )
what is the independent groups design?
There are 2 separate groups of participants. One takes part in condition A and the other in condition B
what are the limitations of the independent groups design and how to deal with the limitations
personality can effect because there will be participant variables
Random allocation can be used using a random number generator to select the participants into groups
What is the matched pairs design
There are two separate groups but they are split into pairs for certain qualities such as age or intelligence. One of each pair does condition A and the other condition B