Research Methods: Research Methods Flashcards
What are aboratory experiments
Aim is to control all relevant variables except for one key variable which is changed to see what the effect is
Conducted in artificial setting
Strengths of laboratory experiments
Control - effects of confounding variables are minimised
Replication- strictly controlled so it can be repeated to check the findings
Causal relationship- ideally it’s possible to establish whether one variable actually causes change in another
Limitations of laboratory experiments
Artificial - experiments may not measure real-life behaviour
Demand characteristics- ppts may respond according to what they think is being investigated, which can bias the results
Ethics - deception is often used, making informed consent difficult
What are field experiments
Conducted outside the laboratory
Behaviour is measured in a natural environment
A key variable is still altered so that it’s effect can be measured
Strengths of field experiments
Causal relationships - can still establish causal relationships, but may be difficult in field experiments
Ecological validity - less artificial than in a laboratory, so they relate to real life better
Demand characteristics - these can be avoided if the ppts don’t know they’re in a study
Limitations of field experiments
Less control - confounding variables may be likely in a natural environment
Ethics - ppts who didn’t agree to take part might experiences distress and often can’t be debriefed. Observation must respect privacy
What can laboratory and field experiments be called
Can be called true experiments as variables can be controlled and manipulated
What are natural experiments
Where the researcher looks at how an independent variable, which isn’t manipulated by the researchers by the researchers, affects a dependent variable
The independent variable is one that occurs naturally
Strengths of natural experiments
Ethical - possible to study variables that it would be unethical to manipulate
Demand characteristics - ppts might not know they’re in a study, so their behaviour is likely to be more natural
Ecological validity- they tend to be less artificial than laboratory
Limitations of natural experiments
Causal relationships - because the independent variable is not manipulated, and because other variables could be having an effect, it’s hard to establish causal relationships
Ethics - deception is often used, making informed consent difficult. Also, confidentiality may be compromised if the community is identified
What are quasi experiments
The researcher isn’t able to use random allocation to put ppts in different conditions
This is usually because the independent variable is a particular feature of the ppts, such as gender or the existence of a mental disorder
Strengths of quasi experiments
Control - often carried out under controlled conditions
Ecological validity - research is often less artificial than laboratory studies, more likely to be able to generalise results to real life
Limitations of quasi experiments
Participant allocation - can’t randomly ppts to each condition, and so confounding variables may affect results
Causal relationships - hard to establish cause and effect because the independent variable isn’t being directly manipulated
What is a double blind trial
Neither ppts or the researcher are aware of the aims of the investigation
Used in drug trials
What is a single blind trial
Ppts are not aware of the condition they are in
Used to control for the confounding effects of demand characteristics
What is a controlled observation
When the researcher has some measure of control over the environment
