Research methods Flashcards
What is an experimental design?
How ppts are allocated to the different conditions (or IV groups) in an experiment
What are the two types of conditions in an experiment?
Control
Experimental
What is the control condition?
Nothing is manipulted so that we have a baseline to complare the results with
What is the experimental condition?
Manipulate IV to see effect on DV
What does IV stand for?
Independent variabele
What is the IV?
Something that is manipulated by an experimenter in order to test an effect
What does DV stand for?
Dependent variable
What is the DV?
A measurable outcome of the action of an independent variable in an experiment
What is operationalisation?
Ensuring that the IV and DV are in a form that can be tested in an experiment
What is an example of an operatinalised experiment?
Addtional testing every Friday leads to higher mock grades in January
What is an example of an unoperatinalised experiment?
More exam practise leads to students getting higher grades
What are order effects?
Refers to the order of the conditions having an effect on the ppts behaviour
What are the two types of order effects?
Practise
Fatigue
What is the practice effect?
order effects
Performance in the second condition may be better because the ppts know what to do
What is the fatigue effect?
order effects
Performance in the second condition may be worse because the ppts are tired
How can a researcher deal with order effects?
Counterbalancing
What is counterbalancing?
The researcher counterbalances the order in which ppts perform different conditions, so although order effects do happen, they occur equally in both groups so balance each other out in the results
What is an example of counterbalancing?
Groups 1 and 2 must complete conditions A and B
Group 1 does condition A then B
Group 2 does condition B then B
What are the 3 types of experimental design?
Repeated measures design
Independent group design
Matched parts design
What is the repeated measures design?
The same ppts take part in each condition of the IV
What is a strength of the repeated measures design?
Less people needed
Less people to find and pay making the experiment quicker and cheaper
This means more time and money can be put into designing a better experiment
What is a limitation of the repeated measures design?
Order effects
This is because each condition of the experiment includes the same group of ppts, so their performance in the second condition may be better as the ppts know what to do (practice effect) or worse because they are tired (fatigue effect)
This means the behaviour may be unnatural and so lacks validity
What is the independent group design?
Different ppts are used in each condition of the IV
How should ppts be assigned to groups in the independent group design?
This should be done by random allocation to ensure that each ppts has an equal chance of being assigned to one group or the other
What is a strength of the independent group design?
Avoids…
Avoids order effects
This means the results are higher in validity as the ppts won’t change their behaviour in different conditions
What is a limitation of the independent group design?
More people needed
More people are needed which is expensive and time consuming to find
What is a limitation of the independent group design?
… variable
Participant variables are differences between ppts in a group, such as age, gender and background
This is a type of extraneous variable
Can affect the results an unwanted way
What is the matched pair design?
Two people with similar qualities are matched up, then randomly assigned to different conditions
What are some examples of similar qualities between ppts in a matched pairs design?
Age
Gender
Ethnicity
Upbringing
What is an example of the ppts in a matched pairs design?
Two 10 year old girls with similar grades and upbringing
What is a strength of the matched pairs design?
Avoids…
Avoids order effects
This means the results are higher in validity as the ppts won’t change their behaviour in different conditions
What is a strength of the matched pairs design?
Reduces … variables
Reduces ppt variables
This is because the researcher matches up the ppts so that each condition has people with similar abilities and characteristics
What is a limitation of the matched pairs design?
More specific people are needed
Very time consuming and expensive to find closely matched pairs
What is a limitation of the matched pairs design?
Imposible to match…
Impossible to match people exactly so ppt variables will still be present
Even identical twins differ in some ways
What is a hypothesis?
A precise and testable statement of what you want to
investigate
What are the two types of hypothesis?
Directional/ one tailed hypothesis
Non- directional/ two tailed hypothesis
What is a directional hypothesis?
There will be a change in one particular direction
e.g. increase
When is a directional hypothesis used?
Directional hypothesis is used if pre- existing research has shown there is a correlation, so you are confident it can only go in one direction
What is an example of a directional hypothesis?
Studying will increase exam results
What is a non- directional hypothesis?
The change could go in either direction
e.g. increase or decrease
What is an example of a non- directional hypothesis?
Studying may change the final grade
What are extraneous variables?
Unwanted variables which may interfere and effect the IV
They should be identified at the start of the experiment and controlled
What is validity?
Refers to how sure a researcher is that only the desired IV (and no other EV) has an effect on the DV
What are examples of extraneous variables?
Age
Gender
Background noise
Difficulty of words
What are the two types of extraneous variables?
Participant variables
Situational variables
What are ppt variables?
Differences between ppts
What are situational variables?
Features of the experimental situation
What are confounding variables?
Does not affect the IV but may affect the DV
This means you could explain the results of the DV with a factor other than the IV
