Give the definition of an experiment?
An experiment is a research method which the effect of two or more conditions of the IV on a DVD is measured, and other variables are controlled, in order to investigate the cause and effect relationship
Give the definition of an IV
The independent variable is a factor in an experiment that is manipulated, changed or compared by the researcher. It is expected to have an influence on the dependent variable.
Give the definition of a DV
The dependent variable is a factor in an experiment that is measured by the researcher. Changes in this factor are predicted to be caused by changes in the independent variable.
What are the levels of IV?
The different conditions under which participants are tested in an experiment that are manipulated, changed or compared by the researcher
What is a control condition?
A condition characterised by the absence of the IV
Why is the control condition needed?
It is used as a baseline for comparison with an experimental condition
Give the definition of operationalisation
The definition of variables so that they can accurately be manipulated, measured or quantified and replicated
Give the definition of a field experiment
A study in which the researcher manipulates an IV and measures a DV in the natural setting of the participants for the activity being tested
Give the strengths of using a field experiment
- Representative behaviour as it is participants normal setting
- Avoid demand characteristics as participants are unaware of the study.
- Has high ecological validity
Give the weaknesses of a field experiment
- Less reliable as control of extraneous variables is hard.
- Study cannot be replicated as procedure isn’t standardised.
- No cause and effect can be established as researcher cannot be sure that the changes in the DV have been caused by the changes in the IV.
- Participants are unaware of the study so therefore ethical issues are raised (informed consent)
Give the definition of a laboratory experiment
A study conducted in an artificial environment in which the experimenter manipulates an IV and measures the consequent changes in a DV, while carefully controlling extraneous variable.
What are the strengths of a lab experiment?
- Everything is manipulated and controlled therefor cause and effect can be established
- Easy to replicate due to high standardised procedures making researchers more confident in their findings
What are the weaknesses if a lab experiment ?
- Behaviour is on representative as it is an artificial setting, participants are likely to share demand characteristics.
- Expensive in order to standardise procedures.
- Lack of ecological validity as it is an artificial setting
What is a quasi experiment?
Experimenter makes use of an existing change or different in situations to create levels of IV (naturally occurring IV) and then measures the DV in each condition
Give the strengths of a quasi experiment
- Naturally occurring IV, allowing investigation into variables that could not practically are ethically been manipulated.
- Participants may be unaware search demand characteristics are less problematic.
- Can take place in any setting.
- Behaviour is more likely to be representative as a natural setting can be used.
What are the weaknesses of a quasi experiment?
- Cause-and-effect cannot be established as extraneous variables are not controlled.
- Hard to find a naturally occurring IV.
- Hard to replicate due to lack of standardisation.
What does an artificial setting allow for?
The experimenter can control many variables that might influence the participants behaviour.
What are standardised instructions?
A set of spoken, written or recorded instructions presented to participants to tell them what to do. This insures that all participants receive identical treatment and information, so differences between their performance on the DV am on likely to be a result of the IV
What are extraneous variables?
Factors other than the IV that could affect performance on the DV
What is a true experiment ?
A researcher can randomly allocate participants to different levels of iv
