Variables Flashcards
What is an operational definition?
Refers to how you will define and measure a specific variable as it is used in your study
What is the experimental hypothesis
A prediction of what will happen
What is a null hypothesis
A prediction that nothing will happen
What is a directional hypothesis
A prediction that the results will go a certain way
What is a 1 tailed hypothesis
When a hypothesis predicts the direction of the results e.g. studying improves exam marks
What is a 2 tailed hypothesis
A hypothesis that does not state a general direction of the results e.g. one variable will certainly influence the other variable
What is an extraneous variable
All the other variables that may affect the results
What is a confounding variable
An extraneous variable that was only noticed after it has affected the results
What are the 3 types of experimental design
Independent groups, repeated measures, matched pairs
What are independent groups
Different people are used in each condition
What are the strengths of independent groups
Demand characteristics are less of a problem
Order effects are less of a problem
What are the weaknesses of independent groups
Participant variables can be a problem
What are repeated measures
The same people used in both conditions
What are the strengths of repeated measures
Participants are better controlled
What are the weaknesses of repeated measures
Demand characteristics may be a problem
Order effects may be a problem but can be controlled through counterbalancing
What are matched pairs
Different people are used but have similar characteristics in each condition
What are the strengths of matched pairs
Demand characteristics are less of a problem
Order effects are less of a problem
Participant variables are better controlled
What are the weaknesses of matched pairs
No two participants will ever be perfectly matched so there may be some participant variables
What is a lab experiment
Its where psychologists investigate human behaviour in an artificial situation
What are the strengths of a lab experiment
Allows investigator to maintain high levels of control
Allows experimenter to easily repeat the experiment for better reliability
Good internal validity
What are the weaknesses of Lab experiments
Lack ecological validity
Demand characteristics
What is a field experiment
The researcher still manipulates the IV but instead of the research being carried out in a lab/artificial setting, it is carried out in the participants’ normal environment
Strengths of a field experiment
High ecological validity
Less chance of demand characteristics
Greater mundane realism
Weaknesses of a field experiment
Less control over variables
Sample bias
Questions over ethics-informed consent
What is a quasi experiment
The researcher does not manipulate the IV but waits for it to occur naturally
Strengths of a quasi experiment
High ecological validity
Ethics are good
Weaknesses of quasi experiment
Selection bias
Internal validity concerns
Less control over variables
