Research methods (experimental method) Flashcards
Experimental method
Involves the manipulation of the dependent variable
Aim
What the researcher intends to investigate; the purpose of the study
Hypothesis
A clear testable statement that states the relationship between the variables to be investigated
Directional hypothesis
States the direction of the difference or relationship
Non-directional hypothesis
Does not state the direction
Variables
Any ‘thing’ that can change within an investigation.
Resulting in changes to another
Independent variable (IV)
Some aspect of the experimental situation that is manipulated by the researcher
Dependent variable (DV)
The variables that is measured by the researcher.
Operationalisation
How variables can be measured
Laboratory experiment
Conducted in control conditions where the researcher manipulates the IV to measure effect on DV
Laboratory experiment advantages
- Control over extraneous variables
- High degree of internal validity causing an effect between the IV and DV
Laboratory experiment disadvantages
- They lack external validity
- Its an artificial environment
- Participants change (behavior)- unnatural
Field experiment
Carried out in natural conditions where the researcher manipulates the IV to measure effect on the DV
Field experiment advantages
- Have a higher level of ecological validity in comparison to lab studies
- Results are accurate of behavior for everyday life
Field experiment disadvantages
- There are ethical issues associated with field experiments
- Research involves their privacy rights
Natural experiment
The researcher does not manipulate the IV and examines the effect of an existing IV on the DV
Natural experiment advantages
Real life situations from using this method
Natural experiment disadvantages
- High in ecological validity given in real life issues that are being studied rather than being manipulated artificially
- There is no control, it is difficult for research to accurately assess the effects of the IV on the Dv
Quasi- Experiment
A naturally occurring independent variable which already exists. Eg. gender, IQ, age or a personality trait
Quasi- Experiment advantages
- No control over the environment & extraneous variables making it difficult to be sure factors such as age, gender or ethnicity have been affected by the DV
Quasi-Experiment disadvantages
Participants cannot be randomly allocated to research conditions remove the issue of bias in procedure
Extraneous variable
Any variable other than the IV that might affect the DV and affect the results
Confounding variable
Any variable other than the IV that may have affected the DV so we cannot be sure of the true source changes to the DV
