Experiments Flashcards
What are the three types of experiment?
- Laboratory
- Field
- Quasi (Natural)
What is a laboratory experiment?
The IV is manipulated by the researcher and the experiment is carried out in a lab or other contrived setting (controlled)
What is a field experiment?T
The IV is manipulated by the researcher but the experiment is carried out using the participants normal surroundings
What’s a Quasi experiment?
A natural experiment where the IV occurs naturally and cannot by manipulated by the researcher (eg. sun)
Advantages of laboratory experiment
- Tighter control of variables
- Easier to comment on cause and effect as setting is controlled
- Relatively easy to replicate
Disadvantages of laboratory experiment?
- Demand characteristics - participants are aware of experiment so may change/alter their behaviour
- Artificial environment - has low ecological validity so its difficult to generalise to other situations
- Experimenter effects - bias when expectations affect behaviour
Advantages of field experiment
- Less artificial as its set in the real world situations (more true to life - ecological validity)
- Valid as people are unaware of experimental conditions and are in their natural environment so act genuinely
Disadvantages of field experiment
- Less control over extraneous variables
- Ethical problems; don’t usually gain informed consent of those involved or they’d give away the aim of the study
Advantages of quasi experiments?
- Useful when its unethical to manipulate the IV
- Studies the ‘real effect’ so there is increase realism and ecological validity
Disadvantages of quasi experiments/
- Difficult to get participants
- Expensive/Costly and takes time because you have to wait for IV to occur
- Confounding experiment variables are more likely so less reliable
What are the three experimental designs?
Repeated measures design
Independent measures design
matched participant design
What is a repeated measures design?
involves the use of the same people in each experimental condition
What is an independent measures design ?
Involves using different people in each condition
What is a matched participant design?
Involves the use of different people in each experimental condition but an attempt is made to make the participants as similar as possible on certain key variables
What is a laboratory experiment?
The IV is manipulated by the experimental and is carried out in a lab or contrived/controlled setting
What is a field experiment?
The IV is manipulated by the researcher but it is carried out in the participants normal surroundings/environment
What is a Quasi experiment?
A natural experiment where the IV is naturally occurring (not manipulated by the researcher
What are the advantages of a laboratory experiment?
- Tighter control of variables
- Easier to comment on cause and effect relationship
- Relatively easy to replicate
What are the disadvantages of a laboratory experiment?
- Demand characteristics - participants are aware of experiment so may change behaviour
- Artificial environment- low ecological validity so difficult to generalise to other situations
- Experimenter effects - bias when expectation affects behaviour
What are the advantages of a field experiment?
- Less artificial - set in the real world situations so it’s more true to life (valid)
- Valid as people are unaware of experimental conditions s and they’re in their usual environment
What are the disadvantages of a field experiment?
- Less control over extraneous variables
- Ethical problems - don’t usually gain informed consent of those involved or they’d give away the aim of the study
What are the advantages of a Quasi experiment?
- Useful when unethical to manipulate the IV
- Studies the ‘real effect’ so there is increased realism and ecological validity
What are the disadvantages of a Quasi experiment?
- Difficult to get participants
- Expensive and requires lots of time and effort because you have to wait for the IV to occur
- Confounding experiment variables are more likely so results are less reliable
What is a repeated measures design?
This involves using the same people in each condition